Proceedings of the 5th International Conference on Industrial Engineering (ICIE 2019)

The article presents the results of a study for gear transmission on parallel axes with gear axoids and wheels in the form of truncated cones (CGA). The tangential gear teeth and CGA wheels in the longitudinal direction coincide with the conical helical lines lying on the truncated cones, which are the axes of the CGA. In this case, the angle of these cones is invariant with respect to the transfer value of the CGA, which allows them to vary widely. The length of the CGA teeth is determined, the growth of which will lead to a decrease in bending and contact stresses in the teeth of the CGA. As a result, there will be an increase in the load capacity of the CGA in comparison with a cylindrical gear transmission with chevron teeth (CGCh) with the same dimensions according to the basic criteria for the performance of this type of transmission—bending and contact fatigue strength. For the practical calculation of the CGA, an enlarged scheme of the algorithm for calculating the CGA is proposed, with reference to the current calculation procedure for the CGCh. The design features of the CGA are noted.

A schematic diagram of the shock-vibration for compacting materials (including hard-to-deform) and the principle of its action based on the lever of Archimedes, which is part of a four-link mechanism, is considered. The article shows the expression for calculating the gain mechanism of the compression mechanism. In the course of work, a mathematical model of the mechanism is described; formulas for the kinematic and force calculation of all links of the mechanism are derived. With the help of the derived mathematical model, it is possible to select the most optimal options for the sizes of links according to the force or dimensional characteristics. The necessary conditions for a successful operation of the new mechanism are described. Its 3D model and general view of the pilot plant, which was designed and installed at SUSU at the Wheeled and Tracked Vehicles department, are shown. According to the tests carried out on it, the technological capabilities and advantages of this mechanism were confirmed in comparison with the vibration compaction technology adopted on modern wheeled or crawler concrete pavers, namely concrete control samples obtained on a molding machine with a shock-vibration mechanism showed an increase in strength of 1.3–1.5 times in comparison with the strength of the samples obtained by a traditional sealing technology.

The choice of the design type of sealing machines depends on many factors: the type of compacted material (soil, crushed stone, gravel, slag, rock coarse soils, asphalt concrete, concrete); the state of the soil (optimal humidity, waterlogged, watering, bulk, subsidence); the thickness of the compacted layers (layer-by-layer compaction thin layers, compaction immediately to the entire thickness of the filling to the design mark); and the working conditions of the machine (cramped working conditions, a wide range of works). The article presents the design of the aggregate for deep soil compaction, developed by the specialists of the Institute of Hydrodynamics “Siberian branch of the Russian Academy of Sciences” (SB RAS). Based on the assessment of the advantages and disadvantages of this unit, a new technical solution based on a cone-shaped roller is proposed, which provides more favorable conditions for the removal of air from the mass of the compacted material. A mathematical model of a cone rollout using the method of decomposition of the periodic function into a Fourier series is presented. The design of a physical model of a cone-shaped roller in the form of a single roller and a self-centering working body with several rollers is considered.

The chapter considers the issue of assessing the effectiveness of technical measures aimed at improving the working conditions of wheeled vehicle operators. A problem is caused by a contradiction between the need to assess the effectiveness of technical measures, on the one hand, and the lack of an objective methodology for their assessment which would take into account the operator working conditions, on the other hand. The paper proposes a solution to the existing problem, which is based on an original method for comparative assessment of the effectiveness of technical measures that contribute to the improvement of working conditions for wheeled vehicle operators. The methodology for assessing the effectiveness of technical measures is based on the justified assumption that technical devices do not equally influence the safety level and conditions of wheeled vehicle operators. The proposed methodology was approved based on comparative testing of the existing and newly developed technical devices of wheeled vehicles. We assessed the effectiveness of the proposed technical devices and compared it with that of their analogs. The implementation of the proposed methodology for assessing the effectiveness of technical measures for the improvement of working conditions of wheeled vehicle operators will improve their safety in the operational process.

One of the factors limiting the development of cattle-breeding in conditions of semi-desert grasslands is the lack of subsaline water resources. In most cases, surface freshwater lenses, opened with relatively dug-out wells, do not give a large production rates. Therefore, the rational use of the well, aimed at obtaining the maximum possible (or required) amount of water, is important, provided that all the requirements ensuring project life and water source safety and reliable operation are met. The main factors influencing the water yield of the well, its condition and service life, are the features of the pumping equipment and operating modes, that is, the modes of pumping water from the well. The task of increasing the water-yield coefficient of a marginal water source can be solved by using water-elevating equipment with optimal parameters and regimes corresponding to the water yield of the water source. The intermittent cycle of joint operation of a water source and a water elevator, expressed in the periodic pumping of water, increases the economic efficiency of the system of mechanized water supply and although it somewhat reduces the coefficient of use of water sources, it provides the needs of objects in water.

The rods of the proposed regulating device (RD) by the means of the drive are tilted relative to its axis and pinch the hose from which the spiral channels are formed. The direct channels of the throttling device in the hose are formed by rods curved in the plane passing through the RD axis. Theoretical studies of the RD with input and output nozzles are performed in the software Solid Works 2017. Experimental studies were performed in the turbulent self-similarity zone. The RD resistance coefficient and the coefficients of friction losses along the length in the input and output nozzles are determined. To visualize the vortex motion of the liquid, air and cut flower petals were fed into the pipe. In the vertical and horizontal arrangements of the RD, the flow of bubbles was located at the pipe axis. In the horizontal arrangement of the RD, the flow of bubbles fluctuated near the axis of the pipe but did not touch its walls. The resistance coefficient of the RD with the direct channels is 6.03, and the area of the middle narrow section is 494 mm2. The resistance coefficient of the RD with the twisted channels made up of is 0.70, and the area of the middle narrow section is 475 mm2. The coefficient of the RD resistance with the direct channels is greater than that of the device with the twisted channels.

The mathematical model for predicting diesel lifetime has been developed. Equations that can be used to determine a relative rate of engine details damage accumulation depending on design, adjustment parameters and load from the objects of application are proposed. These equations take into account inertial loads due to engine speed change, gas pressure in the combustion chamber, heat change and engine parts wearing. Equation for determining the rate of damages accumulation caused by heat changes is proposed. Numerical and experimental studies were carried out, which made it possible to predict a change in the diesel engine lifetime due to a change in its operation modes during adaptation for an industrial tractor. The study results can be used to create diesel engines derated modifications and to develop similar methods for predicting internal combustion engines, which differ in power and objects of application, life time. The calculation methodology, developed on basis of the proposed mathematical model, is used in Chelyabinsk Tractor Plant and South Ural State University at the development of industrial tractor diesel engine modifications.

Although it is shown that in some cases the gear couplings durability is significantly less than the turnaround time of a metallurgical unit according to the criterion of teeth contact endurance. As a rule, this leads to unplanned downtime of metallurgical machines and to additional time and financial costs. In order to solve this problem, there is a need for a preliminary assessment of the couplings life before putting them into commercial operation. For this purpose, the article proposes a mathematical model of gear couplings failures according to the fatigue strength criterion. The model is based on the mathematical formalization of the basic concepts of the reliability theory for machine parts, the basic equation for the kinetic concept of structural damage of materials, and the thermodynamic strength condition of solids. In order to implement the created model, the algorithm and the program “The durability” have been developed, which allows evaluating their average design resource under the specified operating conditions. Using the calculation program, theoretical durability studies of the plate feeder coupling were carried out under the operating conditions of the sintering plant. The resource was estimated for two options for calculating contact stresses: using classical methods of the elasticity theory and considering the finite element method of computer-aided design systems. In the first variant, the prediction error was 24%, in the second—9.7%. This indicates a sufficiently high level of the mathematical model reliability and the correct use of the calculation algorithm at the design stage of machines.

The paper presents the failures of spur gears by the wear resistance criterion of abraded surfaces as one of the main reduction reasons of technical and economic indicators of mechanical equipment. High wear rates of gears lead to an increase in the share of unplanned downtime of metallurgical machines and an increase in labor intensity of repair operations. Therefore, in order to solve the problem of increasing the gear’s wear resistance and durability and to search for appropriate structural and technological solutions in this work, an analytical model of the forming process of their gradual wear failures has been built. The model is based on a basic relationship for estimating the rate of wear-out conjugation elements, obtained as a result of the joint-equation solution of molecular mechanical and structural energy friction theory. The equation for predicting the technical resource of gears is obtained from the condition of getting critical energy density of defects in the structure of the material in the wear products. Based on the solution of this equation system, taking into account the dependencies describing the initial and boundary conditions of the interaction of gearing elements, the algorithm calculating their average expected resource is formulated. It can be used to analyze the effectiveness of various structural and technological methods of increasing the durability of gears and selecting the most appropriate ones. A distinctive feature of the proposed model implementation is the fact that it does not require experimental characteristics of similar linear wear rates, coefficients, or wear factors.

The article deals with the solution of the actual problem of forecasting the technical resource of the most loaded machine parts at the design stage when performing the layout of individual components and mechanisms. This operation is called a control test of parts for durability according to various criteria of their working capacity, and it is intended for comparing the calculated expected resources of elements with the technical specification requirements, which indicates the minimum service life of the machine or individual mechanisms. For this purpose, the article developed a forming process model for gradual failures of the investigated parts according to various strength criteria. It is based on a universal kinetic dependence for calculating the damage rate to the structure of materials under conditions of static and cyclic elements loading over the entire range of stresses and temperatures. The theoretical dependence for estimating their expected resource is derived from the thermodynamic strength condition describing the equality moment of the defect energy density in the most loaded volumes of the critical value. The reliability of theoretical developments is confirmed by comparing the calculated and experimental values of the life of specimens from steel 45 in the annealed condition, subjected to a symmetric loading-tension cycle. The comparison results demonstrated that the prediction error of the average resource does not exceed 35%, which confirms the correctness of the calculated dependencies.

The flexure function $$ W(x,y) $$ of a ribbed rectangular plate is determined by the Kantorovich-Vlasov method on the basis of the sum of series $$ \sum\nolimits_{i = 1}^{n} {W_{i} (y)X_{i} (x)} $$ with functions $$ X_{i} (x) $$ satisfying specified kinematic boundary conditions, while functions $$ W_{i} (y) $$ are determined as the solutions of differential equations of the fourth order. The problem is complicated by the absence of the target selection of functions $$ X_{i} (x) $$ required to attain the desired accuracy. A special beam function $$ X_{1} (x) $$ defined by the initial parameters method was proposed to be used in the first term of series. This function is defined at a single beam with the boundary conditions equal to those of a ribbed plate with respect to the selected coordinate. This allows one to reasonably increase in the accuracy of the specified variation method when one series term is used. The practical calculations of a real object—shaped sheet as per Russian GOST—conducted using the proposed function are provided. Flexure tables were obtained for the shaped sheets provided in the specified standard. The analysis of resulting flexures shows that the use of the sheet profile with more reinforcement ribs is more cost effective as the sheet flexure decreases faster than the sheet weight increases. For example, if one rib is added to S-15-1000-06 profile sheet, sheet flexure in the initial range of 8–12 ribs decreases by no less than 8% with the sheet weight increase by 5%.

The paper deals with a comparative analysis of the stress–strain condition (SSC) of cylindrical gear arc teeth and spurs at different angles of shafts misalignment. The calculation of the teeth SSC was performed using the finite element method under their loading with distributed load on the top edge of the tooth. The laws of load distribution on the top edge of the tooth were established as a result of solving the problems of loading arc and spur gears for different angles of misalignment. The results of the research showed that compared to spur gears, arc tooth gears are exposed to 27% (6′ misalignment) less overall displacements and have 18% (6′ misalignment) greater bending strength and durability in actual service conditions. It allows making a conclusion about the expediency of application of arc teeth cylindrical gears in high-loaded transmissions (for example, in the high-loaded transmissions of electric locomotives EP-100 and EP-200).

Nowadays, piston aluminum–silicon alloys are widely used for high-powered engines due to their low specific gravity, high thermal conductivity, and good castability. However, under the conditions of increase of thermomechanical loads caused by the rise in the specific power output of diesel engines, and the operating temperatures of pistons go up to 0.8–0.9 of the melting temperature resulting in a significant reduction of the Al–Si alloy high-temperature strength. In this regard, to provide a required lifetime of pistons, it is necessary to more precisely simulate their thermal and stress-strain state, taking into account two-frequency loading and inelastic deformation. In this paper, a review of existing methods for the piston life estimation is carried out; a calculation method of the piston transient temperature and strain fields for engine start-stop cycles and one operating cycle at a nominal power mode is developed. The material constants in plasticity and creep models for the Al–12Si–Cu–Ni–Mg alloy are determined. On the basis of the obtained stabilized elastoplastic hysteresis loop, the piston low-cycle fatigue is estimated using the energy criterion. According to experimental data, the piston life is corrected taking into account high-frequency load.

As machine manufacturing develops, the requirements for productivity and accuracy of parts produced on machines become more and more stringent, which, in turn, increases heat generation and adversely affects these parameters. This results in a contradiction between the requirement for machine manufacturing development and machine tool industry capabilities. Basically, it proves impossible to eliminate the contradiction; however, it is possible to reduce the level of confrontation through the creation of a rational design. During design and operation of the machine tool, there is a regular need to evaluate the thermal state of the machine tool. The existing knowledge system uses a qualitative evaluation of the machine thermal state, i.e., “better/worse.” The method has neither a start point nor the measurement unit and, as a consequence, forms a rough estimate of the condition. If there is a need to provide a required level of thermal design state when debugging a test sample at the stage of design development, a method is required that ensures design quantification. This research paper describes a method for evaluating the thermal properties of a structure in quantitative terms. A method based on the developed package of measures consisting of a unit of measurement, standard of this unit, scale of quantitative values, etc. The scope of application of this method is governed by the tasks to conduct a quantitative assessment of thermal properties throughout the life cycle of the machine tool design.

A performance capacity of ring-shaped current collectors is crucially important for power supply systems of various application mechanisms. As a rule, increasing the downforce acting on contact surfaces helps to improve electrical performance values of slip ring contacts and, above all, contact resistance. However, this could lead to the structural failure of the slip ring material and the current collector breakdown. This paper presents a method of analytical estimation of the slip ring stress state in a static setting that would ensure the slip ring mechanical strength. Bending stresses resulting from the slip ring compression and contact stresses at points of ring conjunction with the outer and inner current-collecting rings are considered in the estimation. The estimation results have revealed that bending stresses caused by compression of the slip ring have the most adverse effect on it. The estimation techniques developed for slip rings may be also used both to assess their mechanical strength within existing current collectors and to design new types of current-collecting devices. Comparative evaluations were conducted using the ANSYS application system following the finite element method for verification of the developed techniques, which demonstrated a good level of the repeatability of results.

Reliability of collector rings throughout their service role plays a key role in the performance of power supply systems of various equipment and largely depends on strength and reliability of all of their components, particularly contact rings. One of the most important features of collector rings is their contact resistance. It is usually decreased by using non-ferrous and precious metals and a simultaneous increase of tracking force. However, this approach leads to a sharp increase of stresses within the contact rings. These stresses may even reach or exceed the yield limit of the material and cause its eventual destruction. Nonetheless, performance of contact rings outside the yield limit is possible with using the low-cyclic fatigue area of the fatigue curve. This paper proposes the respective methods of analytical calculation of contact rings’ fatigue and probability of their no-failure performance in plastic state.

The article considers a non-axisymmetric deformation and stability of a compressed aircraft shell. Particular attention is paid to modeling contact interaction of shells with transverse shock-absorbing belts. To analyze shell deformations, we used the iteration method, taking into account a nonlinear change in the reaction of the shock-absorbing belt when there are structure displacements. The shell stability equations were discretized by the Bubnov–Galerkin method using Fourier series. The developed model was used to study the deformation mode of constructively and technologically orthotropic shells exposed to local loads of shock-absorbing belts. The simulation models were verified with the results of testing model and actual shells.

Currently, concern in the development of the Far North and the Arctic has sharply increased. High-power air-cooled diesel engines can be widely used in such severe conditions. In this regard, the problem of determining the possible limits of forcing air-cooled diesel engines becomes relevant again. The solution of the problem was performed by calculation and experimental determination of possible limits of forcing air-cooled diesel engines according to the chosen criterion that defines the forcing limit. As a result, the acceptable levels of forcing air-cooled diesel engines supercharged at different excess air ratios, and the degree of cooling of supercharged air were determined. Based on the analysis of the calculation results, it is concluded that supercharged air-cooled diesel engines are particularly critical to the ratio of the boost pressure to the back pressure at the outlet. It is shown that with an increase in this ratio, the maximum and average temperatures of the injector firing face decrease linearly. The estimation of the possible limits of increasing the diameter of the air-cooled diesel cylinder with different levels of forcing on the average effective pressure is performed.

This article compares the known handbook- and paper-cited reduced geometric rigidities of regular polygon-shaped cross sections in the free torsion of bars against the values of the same parameter obtained by means of integral geometric cross-sectional arguments (the form factor and the conformal radii ratio). In the first case, the construction approximating function returns an approximation to the known values with an up to 1% error; the second-case error is up to 0.5%. The dependencies shown herein can be used to evaluate the torsional rigidity of the cross sections of bar-shaped elements employed in various mechanical systems, robotics, and equipment exposed to elastic deformation.

The paper summarizes the strength calculations made for the frame of the Tourist solar-powered vehicle. The peculiarities of the frame manufacture and its main characteristics were considered. Strength calculations were carried out in ANSYS, as it is a versatile software package that offers considerable functionality for core calculations. For the material model, the researchers picked a bilinear plasticity model with kinematic hardening; the plasticity condition was a von Mises criterion. The frame was rigidly fixed to the front wheel and rear suspension mounting points. A static load of 50–250 kg was set to the seat mounting points. According to these results, maximum static load is 172.5, as exceeding it will cause irreversible deformations. Static load capable of causing destabilization and destruction of the frame equals 228 kg. The obtained results mean it is recommendable to reinforce the lower frame in the seat mounting points in order to reduce the frame deflection. This requires either additional reinforcements or altering the frame configuration whatsoever. Further, research is required to find the most optimal solution.

The researchers have developed a theory of the corrosive–erosive wear applicable to the plates and shells of centrifugal or axial pump impellers; the theory takes into consideration the stress state and the stationary temperature field. Omitting the intermediate calculations, we present a system of differential equations in Marguerre-type partial derivatives on a normal deflection w and a stress function of the eighth order, which describe the stress state of a variable-thickness blade in the context of temperature effects. In this research, the blade thickness change function is set as cubic splines. Analytical solution of the equation system with the boundary conditions is based on using the Dorodnitsyn’s integral ratios method. Pursuant to the method, write the original equation system as a divergent system. Limited to binomial approximation and also choosing power polynomials and their derivatives as weights, apply the integral ratios method to the original system of equations to obtain a system of ordinary differential equations (8n order) with variable coefficients. The boundary value problem is solved by the modified method of successive approximations, developed by Prof. V. A. Pukhliy and published by him in the academic press.

In this paper, the problem of leakage of the medium being compressed in the working part of a single-rotor screw compressor (SSC) with a circumferential tooth shape is considered. The initial system of differential equations of hydro-gas dynamics in relative motion in a rotating system of cylindrical coordinates associated with a cutter tooth of a circumferential profile is shown. It was established that when considering the task, the system of differential equations of hydro-gas dynamics should relate to the thermal and caloric equations of the state of a continuous medium, the dependencies characterizing its viscosity and thermal conductivity, as well as boundary and initial conditions. Reasonably, the simplification of the obtained dependences is possible when evaluating the order of all their members, considering the specificity of the working medium flow in narrow gaps, which takes place in the engagement of the working bodies of a single-rotor screw compressor.

Straight bevel precessional gears with a small shaft angle are a principally new type of bevel gears. It has a lot of great characteristics such as high efficiency due to multi-pair tooth meshing—high torque. A straight bevel precessional gear with a small shaft angle mainly has a wide range of gear ratios (100 and more) and small starting torque compared to worm and spiroid gearboxes. Furthermore, the straight bevel precessional gear with a small shaft angle can better adapt to the oil and gas industry because transmission provides a high loading capacity which is necessary in the Far North and Arctic climates. According to the Hertz contact theory, this paper described the final formula for contact strength of straight bevel precessional gears with a small shaft angle. The contrast analysis of contact strength between the straight bevel precessional gear with a small shaft angle and cylindrical gear and worm gear was investigated by computer simulation. The results reveal that the straight bevel precessional gear with a small shaft angle has a high loading capacity and contact strength in tooth meshing. The results of this paper can be used for the design and production of these types of gearboxes.

The relevance of the paper is due to the need to improve the efficiency of mining excavators. The traditional scheme of a hydraulic excavator straight shovel is considered. Studies have shown that it is possible to increase the performance of an excavator by reducing the weight of working equipment and increasing the bucket capacity while retaining all the advantages of hydraulic excavators and without changing the initial weight of the entire machine, to reduce the weight of the developed scheme of working equipment with a cable-hydraulic drive. The transfer of hydraulic cylinders to the rotary platform of the excavator and the transfer from them of efforts through the cable system provided an exception to the bending moments on the boom and stick, which allows reducing the cross section of these elements and, accordingly, their mass. To expand the scope of hydraulic excavators, studies have been conducted on the creation of a control algorithm for the main mechanisms. Objective: To study the possibility of using a combined cable-hydraulic drive for mining excavators. Research methodology: mathematical modeling of the workflow. Results: A mathematical model, algorithm and program in algorithmic language have been developed for a career shovel with working equipment “direct shovel,” which allows determining the required graphs of the control law of the main drives for shaping the displacement speeds of the hydraulic cylinders ensuring the movement of the bucket along the desired trajectory.

The choice justification of the engineering products concept is carried out on the basis of their quality indicators comparison for various designs including the consumers requirements and expectations, as well as the products of competitors. The various studies main focus is made on the development and application of multi-criteria methods for finding optimal and rational solutions. This paper is devoted to justifying the choice of indicators by which further comparison of alternative options will be made, that is, to the criteria system formation itself. The basis of the quality indicators system formation for engineering products is the relationships setting between their properties, the life cycle stages, and strategies for the implementation of these stages. A method for substantiating the quality indicators system choice which can be used in the qualimetrical differential and complex assessment of the of product quality level is presented. The practical implementation of the methodology for designing a gear pump range with the foundations of the quality indicators selection is considered. The enterprise strategic development plan was developed at the preparation of new products release using the developed methodology.

The authors considered the requirements that should be met by a steel melting unit for the production of cast iron from waste containing harmful impurities. Further, the paper demonstrated the efficiency of using an oxygen converter with a rotating body as a prototype for this purpose. As a result of a comparative analysis of the known smelting systems, a converter with two axes of rotation was used as a prototype for the implementation of the Kalda process, allowing to produce high-quality steel from highly phosphorous cast irons with increased consumption (40–50%) of metal-containing waste. The proposed oxygen mini-converter is advisable to use in combination with a blast furnace with a volume of 110–130 m3 or an oxygen cupola with a capacity of 15 tons per hour under the operating conditions of the foundry of a machine-building plant to produce steel used in the production of castings or forgings. The practical use of the proposed technical solutions will allow steel to be smelted from low-quality cupola iron with partial or full replacement of deficient scrap with metal-containing waste in the conditions of foundries of small engineering and repair plants. At the same time, along with the direct economic benefit obtained, the task of reducing the accumulation in the dumps of industrial metal-containing wastes that adversely affect the environment is being solved.

The feeding system (feeder) of a drilling machine is designed to feed the drilling assembly with the drilling head to the bottom and make the drilling assembly generate axial force acting upon the bottom and operate the drilling assembly. Feeders can use pneumatic, hydraulic, or electric engines alongside with pneumatic and hydraulic cylinders. Feeder mechanisms also can be of various types: screw drives, rack-and-pinion drives, or chain-and-cable drives. The feeder is a part of a drilling machine; when designing an underground drill, design simplicity, reliable functionality, and cost-effective manufacture are the basic criteria of selecting the feeder type. The article considers four feeder types: a screw feeder, a rack-and-pinion feeder, a piston-and-cable feeder and a chain feeder. It presents kinematic diagrams and describe the operation of each feeder, and covering their respective pros and cons. The paper also covers existing types of feeders used in drilling machines: fixed-chain feeders, chain-and-piston feeders, piston feeders with manual interception and two parallel cylinders, automatic-interception feeders with two parallel cylinders, etc. The paper also presents a novel cable feeder designed by the author hereof; the feeder meets the criteria, against which new feeder types must be tested. Find herein the kinematic diagram and a detailed operation summary of this feeder.

The paper considers the accuracy of the formation of engineering products’ surface layers using additive methods. It was determined that in case of additive forming, the accuracy characteristics of the surface layer differ significantly from the accuracy characteristics of the surface layers obtained using traditional methods. This is due to the high values of the error of forming (approximation) in additive methods. To improve the accuracy characteristics of products’ complex surfaces obtained using additive methods, it was proposed to ensure the dynamic spatial orientation of the final element of the additive equipment forming system. To control the spatial orientation of the forming system final element, it was proposed to use mechatronic 5 and 6 coordinate devices. The related area for solving the issues of improving the accuracy of additive forming methods was indicated. This area includes parallel control of the spatial orientation and section dimensions of a single layer, which, at certain values, will form the required value of approximation error at the specified performance. In this regard, the solutions of the problem of the parts’ curved surface approximation by layers with constant and variable sections were proposed. The results of geometric and computer simulation are given. A comparative assessment of the results of solving the above problems is provided. The proposed method will allow reducing the error in forming the products obtained with the help of additive methods.

An imbalance appears during the manufacture, operation, and maintenance of power equipment. The rotor imbalance arises due to the unbalanced masses of the rotor which leads to the emergence of variable loads on the supports and bending of the rotor. The dynamic balancing of the rotor on the balancing machine is the way to avoid the negative effects of centrifugal forces. The balancing machines in resonant and soft-bearing modes are usually used on modern production. However, the soft-bearing method of balancing has a number of shortcomings, which can be solved by using the hard-bearing method. In particular, by using the hard-bearing method, it is possible to balance products with large initial imbalances and to increase the accuracy of balancing. The Autodesk Inventor CAD software was used for modeling of the balancing machine and the rotor. The modal analysis was conducted by using the block method of Lanczos on the basis of the ANSYS. The main assumption during the modal analysis process was that the form of free fluctuations is calculated in relative units and does not allow one to determine absolute shifts. The application of soft-bearing balancing method needs to be added in other ways, taking into account high requirements of the power equipment. A model of a hard-bearing balancing machine was designed for balancing rotors and rotating elements of power equipment. The natural oscillation frequencies of the 3D models of the balancing machine bed and the rotor of the gas turbine engine 16M were calculated to determine the informative frequency range that the rotor should be hard-bearing balanced.

The chapter presents an analysis of the current state and development of snow removal equipment structures equipped with disc cutters for the destruction of strength snow–ice formations on the road surface. For the maintenance of roads in the winter, the most common snow removal equipment is motor grader. The blade of the motor grader provides effective removal from the road surface only the new-fallen loose snow and slightly compacted snow (up to 0.6 m thick). To remove strength and ice formations on the road surface, a combination of several units of specialized snow removal equipment (mechanical, chemical, friction method) is used, which increases economic costs. The urgency is the use of snow removal equipment in the construction of disc cutters. Disc cutters have shown their effectiveness in the working bodies of rotary excavators, rippers, drilling, disc-cutting and earth-cutting machines for the destruction of frozen soils. The construction of snow removal equipment uses cutting disc tools of various shapes and sizes in order to reduce the energy consumption of the process of destruction of snow and ice coasting. The developed construction of the of snow removal equipment with disc cutters and blade is presented. The proposed technical solution will improve the energy efficiency and productivity of the snow removal process without increasing the power of the base machine.

The process of knocking out castings is considered, consisting of removing hardened and chilled to certain temperature castings from the mold, which in this case is destroyed. Shaking out of castings is carried out at various knockout installations, while the main type of equipment for knocking out castings from molds is mechanical knockout grates. In order to improve the efficiency of the knockout process, the design of the foundry knockout grate has been improved. It is proposed to use a coaxial two-rotor vibration exciter of increased power as the vibration drive of the foundry knockout grate. This allows to separately adjust the frequency and amplitude of the oscillations as well as increase the range of regulation of these parameters. It was also revealed that when using this exciter, the load on the supports decreases in comparison with the unbalanced load. The computer and experimental studies of the developed vibration drive have been carried out, and the dependencies of the oscillation parameters on the tuning modes have been determined. The design of a foundry knockout grate with two-rotor coaxial vibro-exciters has been developed.

The basic way of harvesting grain crops is combining where the main role belongs to the combine harvester. One of the most important combine harvester cleaning systems is air and screen cleaning. Despite carried out researches, the world practice has not made essential changes in the classical scheme of air-sieve cleaning. Considering the design of traditional and non-traditional cleanings, it is necessary to note that improving the quality of grain separation, in modern manufacturers, is achieved mainly by increasing the area of cleanings, which leads to an increase in metal consumption. It is possible to raise the efficiency of the separation process technology in air-sieve cleaning, due to its better organization on the finger chaffer on the sieve. The significant disadvantages of the currently used finger chaffer are the low quality of the separation process technology, owing to its low organization, as well as the complexity of the design. This leads to the need for carrying out research and the creating of a finger chaffer, which increases the efficiency of the separation process technology. The article shows a theoretical justification of the design parameters of the finger chaffer, providing a better organization of the heap separation. The design of the original finger chaffer is justified. The results of a theoretical study of the dynamics process of moving components of a heap during sieving on the original finger chaffer are presented. The numerical values of the design parameters of the original chaffer are determined.

The paper describes a mathematical model and an algorithm to compute the stress–strain state of polymeric centrifugal-pump impeller blades. We explore the stress–strain state of a centrifugal-pump trapezoidal anisotropic blade constrained on both sides that are adjacent to plates (median-plane displacement is possible) while not constrained on the two other sides where the blade is exposed to the inertial forces of the blade eigen-weight. Differential equations of bending of a cylindrical anisotropic shell are obtained with respect to the deffection function and the stress function in the field of centrifugal inertia forces. To solve the boundary value problem described by the system of equations in partial derivatives and in boundary conditions, use the Dorodnitsyn’s method of integral ratios. Pursuant to the method, write the original equation system as a divergent system. Further apply the method of integral ratios to the original system of equations in partial derivatives to obtain a system of ordinary differential equations (order 8n) with variable coefficients, which are generally non-Euler. The boundary value problem is solved by the modified method of successive approximations, developed by Prof. V. A. Pukhliy and published by him in academic press. A numerical implementation has been programmed according to the analytical solution above. Computations were run for an orthotropic material of a blade where the principal elastic symmetry axes are turned by an angle φ against the blade axes x, y. The finding of the analysis is that it is necessary to take into account the anisotropy that occurs due to the main axes of the elastic orthotropic material not matching the computed axes of the blade.

This study presents systems with quasi-zero stiffness. The interest in these systems has been constantly increasing recently. In most of the systems with quasi-zero stiffness, the force characteristic with quasi-zero stiffness is obtained due to the combination of systems with negative and systems with positive stiffness. Generally, the length of the working sections of such systems is small and less than few centimeters. The well-known systems with quasi-zero stiffness are observed, main advantages and disadvantages are discussed, and a new classification is presented. Also, this study demonstrated how to upgrade a pneumatic spring into a system with quasi-zero stiffness for increasing their vibration isolating and impact protection properties. For modifying force characteristics of standard pneumatic spring, it is offered to use a pack of Belleville springs. The advantage of such a pneumatic spring with quasi-zero stiffness is the absence of the necessity of its major modifications. Analytical calculations are made for proving such an idea.

The study is devoted to improve the reliability of diagnosing the technical condition of rotary equipment. Nowadays different methods of diagnostics of equipment are used, but the currently applied methods do not allow enough reliable determining defects, because the methods of non-destructive testing use indirect and expert methods of their identification. Moreover, methods usually are focused on some type of defect or a certain part of equipment, so they do not allow identifying any defect. In this study, it is proposed to use an approach to determine the position of the defect according to strain gauges located on the supports of the unit. Information about the location of the defect, together with information about the frequency and intensity of the defect oscillations, allows identifying this defect with high reliability. The fundamentals of the calculation scheme and mathematical model, which allow determining the vertical and horizontal coordinates of the defect by analyzing the dynamic reactions on the supports and phase delays, are presented.

The study aims to address the important environmental problem of reducing the harmful emissions of the exhaust gases produced by preheater-equipped diesel engines when operated in winter. It analyzes the cleaning of prestart-heater exhaust gases in the catalytic converter during the heating of catalyst bricks as the KamAZ-740 diesel engine is being prepared to start. Redirecting the preheater exhaust gases to the catalytic converter cleans them from the products of incomplete combustion and nitrogen oxides while using their heat for the preheating of catalyst bricks. The paper presents the results of studying the composition of exhaust gases produced by the PZhD-30 preheaters used in KamAZ-740 diesel engines. The composition of exhaust gases is found to be the function of the air-excess factor, while the efficiency of preheater exhaust-gas cleaning is determined as a function of the catalyst-brick temperature. It is found out that increasing the air-excess factor from αпп = 1.20 to αпп = 1.60 increases the nitrogen-oxide emissions in exhaust gases 1.64 times while reducing the emissions of incomplete-combustion products: 1.39 times less hydrocarbon emissions, 1.50 times less carbon monoxide emissions, and 1.60 times less particulate-matter emissions. The results of studying the quality of cleaning the preheater exhaust gases in catalyst bricks produced by self-propagating high-temperature synthesis (SHS) show that heating them reduces nitrogen-oxide emissions at 713 K, hydrocarbon emissions at 593 K, and carbon monoxide emissions at 713 K.

Centrifugal electric-driven pumps with the capacity less than 300 W provide circulation of heat transfer fluid within closed loops of a spacecraft thermal regulation system. Taking into account the geometrical arrangement feature of the rotor pump and drive sections of electric-driven pumps, which implies that radial dimensions of these parts are comparable, it is concluded that analyzing rotor friction losses, two types of losses shall be considered separately: friction against butt-end surfaces and friction against cylindrical surfaces of the rotor. In this case, the first type prevails in the rotor pump section, and the second type is primary for the rotor drive section. Calculations show that the rotor pump section makes the largest contribution to rotor friction losses. The main reason is large size butt-end surfaces of the pump section impeller. The paper represents potential friction reduction in the rotor pump section due to increase in the number of electric-driven pump stages and decrease in diameter of each stage impeller.

The analysis of regularities of the change in the stress–strain state (SSS) in prismatic laboratory samples with stress concentrators of the U-shaped grooves is presented. On the basis of numerical simulation of deformation by the finite element method, the dependence of stiffness coefficient of the stress state P and concentration of the equivalent stress Kσ from its basic dimensionless design parameters are determined. The regularities account for a reasonable choice of the geometric parameters of the samples for experimental studies of resistance to static and fatigue deformation in various materials and structural units of various shapes made of them. The calculated estimation of the SSS is carried out by solving the contact problem of deformable body mechanics using the MSC solver NASTRAN and bilinear Coulomb friction model. Analysis of the results of computational experiments showed that when the values of the relative angle of the support surface do not exceed 20°, the account of forces of friction changes as the values of maximum contact pressure on the contact surfaces and the maximum value of the stress intensity in the working area of the considered samples are not more than 5%.

The paper is devoted to the study of behavior gears’ wear parameters after burn-in period, to obtain reliable data about behavior of gear drive, to simplify development of new gears by reducing the number of test cycles, due to the given measurement and calculation data. The article provides a brief description of the automated device for study of gears, on which the measurements of parameters of gear engagement were held. The software, which is specially developed for processing of results of measurements of the device in the automatic mode, carried out necessary calculations with displaying all necessary parameters for a research of impact of wear in transmission. During the experiment, gears with various quantity of teeth were tested, and couples of interaction were chosen so that to capture the big range of the transfer relations. The results of measurements and calculations are presented in graphical form, which allows demonstrating the dynamics of their changes. Due to the large amount of statistical data, at the end of the paper conclusions were drawn about the applicability of the results obtained, using the developed measurement methods, as data for the calculation of gears and gearing.

Mechanical stirrers are widely used in chemical, petrochemical, food, construction and many other industries. Currently, a large number of stirred tank actuators with various types of the impeller motion have been developed, and at the moment the most promising constructions are rotationally reciprocating stirred tanks, since they make it possible to ensure high intensity of heat and mass transfer processes in the reactor, to eliminate stagnant zones and to increase the velocity gradient of the stirred liquid. As an actuator, the author proposes to use a planetary gear with elliptical gearwheels, which allows to convert the rotational motion of the motor shaft into a rotationally reciprocating motion of the impeller. For the design and manufacture of stirred tank, it is necessary to investigate its kinetostatics. In the article, the force analysis of the planetary actuator of the mixing device was carried out, as a result of which the design schemes were obtained and expressions were found for determining reactions in kinematic pairs. This will allow further calculations of the elements of kinematic pairs and links for strength, as well as determining the efficiency of the actuator.

The design of the shell and tube heat exchanger includes a tubelike shell with holes to which an inlet and outlet pipes are welded. Radial and tangential holes are produced manually by means of plasma cutting with the use of specialized tools, which determines high laboriousness of heat exchanger production. An automatic device is proposed to reduce the laboriousness of this operation. To produce the hole in the heat exchanger shell, two reversible motions are superimposed: linear motion of the cutter along the longitudinal axis of the shell and the shell rotary motion. A mathematical model of the required cutter motion is proposed, which describes the relative trajectories of the plasma cutter and the shell in parametric form. To verify theoretical premises, a prototype of the device was produced using a 3D prototyping technology, a ball screw for the reversible linear motion of the cutter and a stepper motor for the reversible rotary motion of the shell. The shell is fixed by means of a collet chuck and rests on the pipe roller support. The principles of automatic control of the linear and rotary motions of the cutter and the shell are proposed, based on the 3D model of the shell.

The article describes a new method of cooling system searching design, which is based on the physical working principle graph model, based on the thermodynamic description of physical processes. The rationale of the physical working principle graph model has been presented, and basic theoretical propositions concerning the semantic load on the vertices and edges of the graph have been shown. The necessity and sufficiency of this physical working principle graph model for this class of devices have been confirmed by modeling the physical working principle of a technical solution for device for cooling the cutting zone of a milling machine. The example of technical solutions for device for cooling the cutting zone of a milling machine plurality obtainment has been represented. The method can be applied as a means of enhancing the labor efficiency of designers at early stages of designing owing to reduction of labor expenditures when choosing the concept of an engineering system for refrigeration and also as a methodical support for the development of computer-aided design systems.

The article deals with the problems of creating new types of fuels based on the processing of renewable forest bioresources and ways of processing wood materials into gaseous, liquid and solid fuels. Solid biofuel, in the form of pellets, is becoming widely used, its production is expanding annually, and that is why much attention is paid to increasing the quality of this type of fuel. KNRTU is conducting research on the integrated processing of wood biomass into liquid and solid fuels. A flow chart of integrated processing of wood biomass into liquid and solid fuels is presented. The authors considered an installation for the production of thermally modified pellets with high heat of combustion. The results of mathematical and physical modelling of thermal modification of pellets obtained by adding lignin are presented. The kinetic curves for the decrease in the specific mass of wood pellets under different temperature conditions, the dependence of the non-condensable gas composition on temperature, the dependence of the heat of combustion of wood pellets on the temperature of the thermal modification process and the concentration of lignin, and the dependence of the hardness of pellets on the initial concentration of lignin are presented. The technology for the production of solid biofuels—thermally modified pellets consisting of shredded wood and lignin—has been developed.

This article shows the results of studies of heat transfer in the furnace of a DKVR-10/13 steam boiler. The studies were performed using numerical simulation methods. The influence of the computational method of heat exchange by radiation, as well as the spectral model of radiation on the simulation results, was studied. Monte Carlo and discrete transfer methods were chosen as the methods for calculating the heat exchange of radiation. The number of stories and rays for the Monte Carlo and discrete transfer models was 50,000 and 8, respectively. A simple gray-gas model and a weighted-sum gray-gas model were chosen as spectral radiation models. A total of four calculations were performed. For each variant studied, the radiation intensity, maximum temperature, heat removal from the screens, the gas temperature at the outlet of the furnace, and the temperature distribution of gases along the height of the furnace were estimated. Using the engineering method, the results are compared with the results of calculations.

The article suggests a method for providing an efficient operation of automated devices in a truck drive axle. An automated blocking of interaxial or inter-wheel differentials eliminates any chance of power circulation occurrence or additional loading of transmission units which makes part service lives longer. The information space of a drive axle control system is determined by external (environment, road) and internal (engine, drive) objects subject to influence each of which can be characterized by a finite number of factors. A drawback linked with a necessity of blocking manual control can be overcome if friction clutches are used as automated mechanisms. The authors present the results of their research of the truck drive axles’ operating condition under various conditions. Special emphasis is put on the operation of cars in wintertime. Maintaining the temperature of oil and drive axle parts within a rational range of values provides for an increase in the transmission unit operation efficiency. A possible option is to convert the heat energy of burnt gases into electric power with a subsequent electric power transmission and reverse conversion of such power into heat just in the section of a drive axle.

A simulation of the magnetic control system structure of microparticles based on permanent magnets was carried out. Computational experiment results for magnetic field calculation created by the simulated system are presented. Comparative estimates of modern software environment’s accuracy based on the finite element method and the SEM software package based on the standard element method are obtained. The authors continued the development of numerical and analytical methods of standard elements and auxiliary functions for the modeling of physical fields in a piecewise-homogeneous and nonlinear media. The introduction of standard elements opens the possibility of applying methods of auxiliary functions and standard elements without combining them with the finite element method. The use of standard elements provides a good approximation of an outer boundary of the computational domain, the interface of its parts with linear and nonlinear properties and complete filling of the computational domain standard elements. Functional representation can be expressed in terms of the nodal values of the solution imposed on the boundaries of standard elements for their bonding with adjacent standard elements.

This paper presents the results of experiments and calculations of a universal solid fuel boiler that allows one to dispose of waste of hazard class 4–5. A fundamentally new design solution of the furnace chamber and boiler heating surfaces is proposed. A distinctive feature of the proposed design is an inclined sieve that allows the airflow to evenly distribute the burned material in the space of the combustion chamber. As a result of the calculation the optimal shape and size of the sieve were obtained, which allows increasing the efficiency of the combustion process by reducing the time of complete combustion of up to 26%. It is shown that the use of a special screen made of refractory material makes it possible to optimize the directions of movement of the burned material, blast air and combustion products. The heat obtained in the combustion process is used in the cycle of the biogas plant to compensate for the thermal losses of the methanogenesis reactor, which allows ensuring the stability of the plant in the winter period.

Analytically, on the basis of the differential equations of material balance, the equations of working lines and mass transfer in the distillation column for binary mixtures for the strengthening and exhaustive parts of the packed distillation column with a diffusion structure of the flow in a continuous liquid phase are derived. Comparative examples of the calculation for typical structures of the flow of ideal displacement are given using the derived equations that take into account the longitudinal diffusion for a “ethanol–ethyl alcohol” binary mixture. A calculation algorithm is proposed, and technological and geometrical parameters are compared with similar parameters of the same column and are calculated according to a typical algorithm, when the dispersed gas phase has the structure of an ideal displacement flow, and the continuous liquid phase is an ideal mixing. The scheme of material flows and their concentrations is presented in the exhaustive part of the rectification column taking into account the longitudinal diffusion.

A general outline and description of the operation of an automated rotary chopper for horticultural raw material have been presented. Theoretical researches of cutting operation with the device proposed have been carried out, with obtaining a relevant mathematical model, as well as a simplified theoretical model the algorithm of which has been implemented in a computer program. An experimental model of a rotary horticultural raw material chopper has been developed and made. The knife approach angles, as well as the cutting forces of raw materials to be processed with various knife layouts, have been experimentally defined. The experimental data obtained have a high verifiability with mathematical models where the divergence between similar indicators does not exceed 5%. A positive effect of using the chopper includes lowered power consumption during the operation, as well as the minimum destruction of the structure of raw materials processed and high productivity. As a result of the research carried out, methods and calculation algorithms allowing to qualitatively estimate the dynamic condition of the material being processed have been developed and that enabled to analyze the condition of the equipment proposed and achieve rational design parameters and operating modes.

Ensuring the accuracy of the print head positioning plays a significant role in improving the quality of additive parts. However, the factors influencing the accuracy of displacement systems are not sufficiently investigated. The article provides an overview of kinematic schemes of movement of the print head of 3D printer: H-Bot, CoreXY, Markforged, and Ultimaker. According to the schemes considered in this article, the equations of displacement of the print head depending on the direction of rotation of the engines according to these schemes are determined. The authors presented design schemes to determine the rigidity of the leading part of the belt in the longitudinal and transverse movement of the print head in kinematic schemes H-Bot and CoreXY. In the course of the research, dependencies were obtained. Graphs of the accuracy of displacement from the design and operating parameters of the H-Bot and CoreXY kinematic schemes were constructed. The conclusions about their impact on the error are formulated.

The article proposes an algorithm for creating parametric 3D models in CAD software using the integration of results of calculation performed in PTC Mathcad. This method may be used to parameterize 3D models, the geometric dimensions of which are determined by complex mathematical formulas associated with the choice of values from tables, standard series, and observance of various conditions and constraints, using logical functions. The research authors have performed a complete automated calculation of an enclosed gear using PTC Mathcad components and have integrated the calculation data into a parametric 3D model of the housing and connected parts created in a CAD software. As a result, a parametric 3D model of the assembly was designed, with automatic geometry updating based on the results of automated calculations. The parameters of the 3D model are controlled by changing the input data in the Mathcad file. This paper presents the examples of studies that were carried out using the developed algorithm. These are the series of graphs and tables of the obtained sizes and masses of gear housings in a wide range of variable input data such as gear ratios, transmitted torque, hardness of the gear pair materials, and a given service life. The developed algorithm for parametrization of 3D models can be used to design a product line of similar configuration, to solve multivariate analysis and design optimization problems and to reach research and development objectives.

This article is devoted to the creation of elements of a CAD system for internal combustion engines designed for the automated selection of parts for multi-bearing bearing units with more than 4 supports. The basic principles of the proposed approach, based on the use of modified procedures for selective assembly, multiples of the calculation modules consisting of 4 pillars are considered. The article proposed a methodology for determining the optimal assembly option using an automated process control system for assembling multi-support shaft support nodes. It includes a methodology for creating databases and aims at stabilizing the gaps of multi-support shafts. It uses a geometric modeling system based on an invariant computer-aided design system. The proposed method is aimed at organizing diametrical gaps in the range from the minimum functional gap to the optimum. It is also intended to ensure the limits of the minimum and optimum thickness of the oil layer when assembling a multi-support unit of the support shaft and also to ensure reserves for wear and serviceability by compensating for the actual errors of mechanical processing and individual assembly.

Possible ways of improving the accuracy of topology elements in laser pattern generators based on the circular scanning principle are analyzed. The most important sources of errors induced by the system of radial displacements and by the rotation of the rotor of the mechatronic module are studied. For the image generators with circular scanning, the principles of decreasing the main components of the operation instability are described. The method of improving the accuracy of the same generators is proposed. The result is achieved by using two hybrid angular encoders and two-coordinate deflector in it. The use of hybrid angular encoders allows making measurements of the turning angle and current radial deflections of the angular coordinate laser pattern generator rotor axis simultaneously. For that two measuring patterns, radial raster for measuring angular displacement and ring for measuring linear shift raster in a tangential direction are formed on a single glass basis for one technological process. The use of a two-coordinate deflector allows one to make the correction interaction of the laser beam with the photosensitive material.

The energy and heat losses reduction in the process of fuel combustion enables the diesel engines’ power and fuel efficiency growth by improving the operating cycle indicators. The fuel combustion process efficiency depends on the completeness of the emission and use of the burning fuel heat. The most important factors that determine the level of heat losses are the combustion process duration, the fuel-air mixture composition, and the crankshaft rotation frequency. It is established that the combustion efficiency coefficient increases with the reduction of the combustion process duration; the more intensive the coefficient increase, the lower the crankshaft rotation speed and the greater the excess air ratio. The factors’ influence on the combustion process efficiency is determined from the thermodynamic analysis results of the gas pressure indicator diagrams in the diesel cylinder.

To the accumulating type fuel system, a study of fuel delivery processes for low-temperature start-up conditions was performed. The quality deterioration of fuel atomization occurs as a result of the injection pressure decrease and the back pressure in the combustion chamber at low cranking speeds of the crankshaft. Lowering the temperature, increasing the viscosity of the fuel affects the quality of atomization. As a result of the enlargement of fuel droplets, a significant part of it falls on the cold walls of the combustion chamber. The authors estimated the influence of low temperatures and pressures in the high-pressure line of the system on the characteristics of fuel injection and atomization in the combustion chamber. To improve the quality of the distribution of fuel in the volume of the combustion chamber allows multiphase injection. Local fuel heating in the nozzle may have a great influence on the starting characteristics of the diesel. This contributes to a better distribution of fuel in the combustion chamber volume, crushing the fuel into smaller droplets, reducing the time for heating and evaporation of the fuel.

The paper describes the solution of the problem of determining the relationship of the main design parameters of the motion conversion mechanism with the design and technical parameters of a crankless reciprocating machine (engine) and identifying the influence of these parameters on the machine performance, as well as the value of the developed torque on the output shaft as compared to the crank-rocker internal combustion engine. The comparison is made based on the similarity (identity of the parameters characterizing the conditions for the implementation of the working cycle of a heat engine) of the working processes flowing in a cylinder of a crankless machine and a crank-rocker engine. A conclusion is made on the advantage of the crankless machine concerning the design of high-torque engines. Practical recommendations are given on the choice of design parameters depending on the technical requirements, the purpose, and sphere of application of the crankless machine.

There was a need to install additional ventilation equipment with its takeaway on the workshop roof due to change of production schedules. The research showed that the change of a design scheme of bearing structures with organization of additional nodes which it leans on is the way for provision of safe work. This article is researching a dynamic load on bearing structures which is observed at working with additional ventilation equipment. The spectrum of natural frequencies of oscillations was determined. The values of these frequencies were compared with the frequency of forced oscillations of the equipment. The graphs of changes in the spectrum of natural frequencies are constructed when the fans reach the working frequency. According to the graphics, when the frequency of the driving force coincides with the frequency of natural oscillations, the inertial forces increase sharply which indicates the passage of the resonance zone. There was a research of change in dynamic forces due to rotor imbalance. A gap was found that occurs when bearings are worn which will lead to the destruction of the supporting element of the farm.

The paper presents the results of an experimental study of the influence of a turbocharger turbine on the thermal and mechanical characteristics of gas flows in the exhaust system of a piston internal combustion engine (ICE). The experiments were carried out on a full-scale model of a single-cylinder engine under the conditions of gas-dynamic non-stationarity (pulsating flows). The article describes the laboratory setup and the methodology for conducting experiments. The analysis of the dependences of the instantaneous velocity and pressure of the pulsating flow, as well as the local heat transfer coefficient in time in the exhaust pipe of the piston engine with and without a turbocharger (TC), is presented. It is shown that the placement of the TC turbine in the gas-air path of the piston ICE significantly affects the gas-dynamic, flow and heat exchange characteristics of gas flows in the exhaust system. The installation of the turbocharger causes restructuring of the structure and flow regime in the exhaust system.

The article presents the results of upgrading a diesel locomotive engine with turbocharging and a cylinder with the diameter of 210 mm and a piston stroke of 210 mm through changing the valve timing (based on the Miller cycle). The research was carried out with numerical simulation in the ACTUS programme and based on experimental studies of test benches at the Ural Diesel Motor Plant. In the course of mathematical modelling, the hypothesis of the positive effect of an early closure of the intake valve on the diesel engine’s environmental performance was tested. It has been established that an early closure of the intake valve leads to a reduction in NOx emissions in exhaust gases by up to 20% with a slight change in power and specific fuel consumption (±3%). Based on the experimental research on diesel performance, comparative harmful emission diagrams for the basic and upgraded engines (NOx, CO and CH) are constructed. It was experimentally established that the change in the gas distribution phases (based on the Miller cycle) leads to a 16% decrease in NOx content, a 50% reduction in CO and a 54% reduction in CH. At the same time, a decrease in the specific effective flow rate reaches a value of 3.3% for certain operating modes of the diesel engine. The values obtained for the concentration of harmful emissions in exhaust gases are substantially lower than those required by international standards.

We considered the possibility of calculating the temperature ranges of the fresh charge heating degree, which provides favorable conditions for the self-ignition of the combustible mixture in the diesel cylinder at the end of the compression process, as applied to the “cold”-start conditions. We developed a method to determine the degree of the fresh charge heating and the degree of its oxidizer (air oxygen) impoverishment. We studied that the influence of the degree of the intake air heating on the duration of the diesel engine starts at low ambient temperatures. We calculated that the degree of heating is 40–50 degrees for the ambient temperatures from −30 to +5 °C, which ensures the fluid temperature of 287–315 K at the end of the intake. It has been established that the duration of the diesel engine start is reduced intensively up to a certain value of the intake charge heating degree (a 40–60-degree temperature increase), and then, the influence of heating becomes less significant. Thus, at the ambient air temperature of −30 °C, a 60-degree air heating in the intake manifold allows us to reduce the time spent to start the diesel engine from 43 to 22 s. With a further increase in the degree of heating, this time varies slightly.

The tendency of scientists and engineers to enhance automobile safety led to appearance of high-safety wheels able to keep stable and steerable vehicle movement at the loss of excess air pressure even in several pneumatic tires. In case of loss of excess pressure in one of the pneumatic tires, the modern high-safety wheels producers guarantee safe non-stop vehicle running at a speed up to 80 km/h for a distance within 200 km. However, the loss of excess air pressure even in one pneumatic tire results in noticeable deterioration of factors for majority operational properties including smooth running specified by the automobile sway intensity when running on the uneven surface roads and under off-road conditions. Scientific studies aimed at the enhancement of smooth running and keeping vibration loading levels to normative limits for cars forced to continue movement without the excess air pressure in one or several pneumatic tires ensure their urgency.

This article specifies the numerical description of the closed curve using the Fourier series. Fourier analysis of closed curve is used in order to find the appropriate guidance mechanism by electronic catalog. This method is based on optimization methods and allows taking into account the additional requirements of synthesis and limits. The most important role in the study of problems including their computer modeling is assigned to the methods of presenting the obtained results and, above all, the methods of graphic imaging and visualization of the phenomena under study. The main method of computer modeling is writing of proprietary software in algorithmic programming language C++, which gives a fundamental versatility of possibilities and direct comprehension of computer-oriented nature of the used modeling methods. By taking into account the identified shortcomings, it was formulated the setting of research problems, the solution of which allows achieving the goal to be sought—the method for representing of lever mechanisms in the database using Fourier series coefficients for decomposition of the mechanism coupler curve. The methodology offered in this paper represents an effective way to select the first approximation for the synthesized mechanism that allows, on the one hand, the most effective way to create the library of mechanisms and quickly find the right mechanism.

The article presents the results of a mathematical model and software development for numerical simulation of fuel ignition chemical kinetics in a diesel engine combustion chamber at cold start with Modelica language. The study aims at ensuring that diesel engines meet the requirements of regulatory and technical documents for starting characteristics. In the course of the study, the mathematical model of the fuel ignition and combustion chemical kinetics in the diesel engine combustion chamber, which can be used for starting characteristics predicting, was created and implemented as software. In the course of numerical studies, it was determined that to ensure ignition of diesel fuel in the combustion chamber, the required value of local gas temperatures should be at least 1350 K. The permissible proportion of carbon dioxide in the gases, when engine can start, with simultaneous intake air heater operation, should not exceed 40%. The developed mathematical model and software are used in current research and development work of South Ural State University to create new and modernize existing diesel engines of various types and purposes, produced by Chelyabinsk tractor plant.

This article studies the dynamic pattern of safe (hazardous) operation indicators for heavy-duty machines. A load-carrying structural member of metallurgical overhead crane with a frame manufactured from 09G2S steel and having 50 ton lifting capacity was selected for the study. A generalized limit-state equation for the structural crane element represents hypersurface, which distinguishes the safety zone and the hazard zone. Safety and hazard functions are presented as integral functions of probability distribution density, resulting from various factors that affect the likelihood of occurrence of emergencies, accidents and machine breakdowns. The indicators with the greatest influence on the probability of safe and hazardous states of the structural element or the structure itself can be identified. It is accepted to investigate probabilistic features of stress and deformation fields. The stochastic boundary-value problem of the structural element’s stress–strain behaviour under random load is addressed in this case. The problem can be resolved by obtaining correlation and spectral functions of stress and deformation under given load functions. Considering that heavy-duty machines are operated in steady state, it can be assumed with sufficient assurance that such random processes represent steady Gaussian processes. The probabilistic dynamics of safe operation indicators are studied by using computer-based simulation modelling. The obtained modelled curves of probabilistic machine load allowed one to deduce equations of stress and deformation probability density. Every coefficient of the obtained models is probably significant based on Fisher’s criterion. The obtained relationships allow one to construct graphs of limit and acceptable states when evaluating durability and operating life of heavy-duty machines and the probability density for operating and rupturing loads and stresses.

A mechanorheological viscoelastic–plastic model was applied to study the influence of a spherical body diameter on the impact duration. With an increasing spherical body diameter, the body mass and the surface curvature radius increase. Simultaneous and separate effects of both factors were studied. Impact interaction was simulated using a mathematical model. The study identified that a simultaneous increase in both factors (body mass and surface curvature radius) increases the impact duration. An increase in the body mass leads to a more significant increase in the impact duration because at the same initial impact speed, body deformation and deformation time increase. An increase in the surface curvature radius decreases the impact time because of the rigidity of the elastic body, i.e. elastic resistance to deformation, increases in the deformation zone. At the same initial speed, body deformation and deformation time decrease. Therefore, under the simultaneous influence of two factors, an increase in impact duration is less significant. At various values of model parameters, an increase in plasticity increases impact duration. This phenomenon is accounted for an increase in full deformation and impact time due to the influence of the plastic unit. Thus, the mechanorheological model identified that impact time depends on impacting body parameters (mass and surface curvature radius) influencing the dynamics of body movement and deformation. To improve simulation and research result accuracy and reliability, it is necessary to account for the influence of these factors on the dynamics of impact interaction when solving practical tasks.

The permanent increase in the octane number of gasoline fuel is one of the modern ways of developing the building and exploitation of internal combustion engines. Increasing the gasoline’s octane number brings to perfection of exploitation properties of gasoline engines with a simultaneous improvement of proof from detonation processes. The nomenclature of fuels with different octane numbers is quite wide. There are the fuels with octane number 92, 95, 98 and even 100 with different additives and components. However, till now, the information about exact parameters of an operation cycle using the fuel with an octane number of 100 units in comparison with other types of fuels is not enough. In this investigation, the indicative and efficient parameters of the engine’s operating cycle are estimated and analyzed by means of an experimental test-bench machine and using the fuels with different octane numbers. The gasoline fuels with octane numbers 95 and 100 units are analyzed with indicative diagrams and various ignition timing. As a result, the duration of a combustion process as well as the values of maximal pressures and temperatures is received for different types of fuels. The conclusions on the results of investigations are proposed and represented.

The article presents a mathematical model of the interaction of an elastic wheel with bumps of a rectangular shape. In the study of the process of movement of a wheeled machine is of great importance to calculate the forces applied to the wheel of the vehicle. These forces determine the nature of the movement of the wheeled vehicle. With an increase in the speed of wheeled vehicles and the deterioration of road increase the dynamic load on the elements of the running system. In this regard, there is a need to develop a mathematical model describing the interaction of the wheel of the wheeled vehicle with the road. The proposed mathematical model describing the rolling of a wheel equipped with a pneumatic tyre through a rectangular obstacle can be used for practical calculations. The results of the calculation are in good agreement with the results of experimental studies, taking into account the complexity of the processes and fairly rough assumptions. The average error of calculation of forces of interaction of a wheel with an obstacle of the rectangular form makes 7.71%.

Composite materials (CM) along with metals at present are widely used. They are characterized by the anisotropy of the mechanical properties, so in some cases CM can be considered as orthotropic materials. Orthotropic materials are characterized by the presence of three mutually orthogonal planes with symmetry properties in each elementary volume. For example, such materials can consist of a plastic binder (matrix) reinforced with fibers, possessing high strength, rigidity, etc. The combination of heterogeneous components leads to the creation of a new material with quantitatively and qualitatively different properties from the original properties of its components. This paper develops a new numerical method based on two-dimensional spline functions of degree 5 defect 1, which allows obtaining the calculation results of the stress-strain state of orthotropic plates with high accuracy. The paper presents a method for constructing a discrete analogue of the differential equation for bending of an orthotropic plate, forms a number of exact solutions for test problems, solves test problems using the numerical spline method, compares numerical solutions with exact ones, and presents quantitative accuracy estimates of the proposed spline method.

Simplicity and high efficiency of a wheeled mover as a mechanism for converting rotational motion into a translatory one have conditioned its wide application in overland machines including motor vehicles. However, a wheel with a non-pneumatic tire has a sufficient drawback lying in termination of a wheeled machine movement at the excess air pressure loss. Moreover, the loss of excess air pressure in a pneumatic tire of traditional design at high speed of movement of a motor vehicle can lead to a traffic accident with heavy consequences. This problem is particularly acute for military purpose motor vehicles as under conditions of combat actions a motionless vehicle becomes a convenient target for grenade launchers and aimed fire of small arms which to a considerable degree influences the chances of military servicemen to stay alive and fulfill the operational mission. The stop of a motor vehicle to change a wheel on a heavy traffic roadway or roadside also poses a threat. These reasons determine the necessity of both well-known design improvements and search for the new wheeled mover design solutions to enhance a motor vehicle safety, the use of wheels with non-pneumatic tires of elastic polymeric materials being one of them. Safety enhancement by means of non-pneumatic tire use along with keeping the high performance of wheeled machine operational properties is an important scientific and technical task that determines the research urgency.

The authors carried out the mechanical and mathematical modeling of the motion of a pendulum mounted with the possibility of free rotation on the rotor shaft of an electric motor fixed in housing on elastic supports. The peculiarities of the motion of the pendulum within the range from zero to a given value of the angular velocity of the rotor of the electric motor with the presence in this range of natural frequencies of oscillations of the mechanical system are revealed. It is established that when changing the friction moment in the pendulum support or the pendulum mass, a mode of movement is possible and when the rotor rotates with a given angular velocity, the angular velocity of the pendulum rotation is equal to one of the natural frequencies of the mechanical system. The results of a numerical experiment conducted for the first time in a mechanical and mathematical modeling of the motion of a pendulum on a rotating shaft confirmed the results of a previous full-scale experiment on the possible emergence of a pendulum “sticking” effect for such mechanical systems of a general form.

The article is devoted to the problem of reducing the dynamic loads in the hoisting mechanisms of an electric mining shovel. In this article, by the example of the EKG-8I excavator, the results of studies of the electric drive control algorithm of hoisting mechanisms based on feedbacks on the elastic torque in the hoist cable, allowing one to limit the value of this torque, are presented. In this case, the synthesis of control algorithms is based on the solution of the inverse dynamic problems according to the given law of elastic torque variation, which allows directly determining the structure and parameters of feedback. The equations of motion of the electromechanical system of the hoisting mechanism of the excavator and the results of numerical simulation confirming the effectiveness of the proposed control algorithms are given. It is shown that the synthesized feedbacks allow reducing the dynamic loads in the hoisting mechanism of the excavator and to approach the curve of change of the elastic torque to the shape of the mechanical characteristic of the excavator drive. Possible ways for implementing the proposed motion control algorithms are discussed.

Railroad transport has a leading position in the country’s transport network. Similarly to land transport, rail wheels do the following: braking, rolling, and load transmission. The reliability of a wheel-rail system has a direct impact on the traffic safety. Major energy losses in the mechanical part of a rail-mounted locomotive account for the wheel-rail contact region. Hence, the wheel/rail interface is considered fundamental to the performance of railroad transport. The article considers the results of studies of the distribution of the magnetic field between the wheel and the rail, the criteria for evaluating the efficiency of magnetization of the wheel-rail contact zone. It was found that the saturation of the contacting surfaces of the wheel and rail occurs in different ways. For the saturated state at the two-point comb contact, the greatest value of the magnetic field induction on the crest is less than the induction on the riding surface. For the saturated state in the presence of an air gap between the wheel crest and the rail, almost all the magnetic flux is redistributed to the surface of the wheel.

Life service forecast of the hopper car body welded load-bearing structure of the design loading in operation is made on the basis of mathematical modeling. The elastic properties of the car body are taken into account when modeling the load alongside the longitudinal forces appearing in the process of car’s movement when a part of the train or shunting is specified. The problem is solved in a dynamic formulation by using hybrid dynamic models of cars movement in conditions of real railway track irregularities and detailed plate finite element models. The fatigue life of the most loaded load-bearing structures of the hopper car was assessed within the framework of the determined Serensen-Kagayev model of multicycle fatigue, which is the basis of the normative calculation. In assessing the durability of the welded load-bearing structure of the body, using the updated methodology, the authors evaluated the influence of stress concentration in the area of welded joints.

Through the synthesis of the working cycle, the nature of changes in the pressure and temperature of gases in the engine cylinder is determined. According to the results of the kinematic and dynamic analysis of the crank mechanism, the resulting force acting on the piston and applied to the axis of the piston pin is determined. The estimation of the thermal and mechanical loading of the engine piston 4CH8,2/7,56 was carried out, when forcing at the average effective pressure using a universal method for estimating the boundary conditions, allowing to take into account all the components of the heat balance and gas-dynamic loading features during the working cycle. Evaluation of the thermal state of the investigated piston at steady-state operation is reduced to determining its temperature field in the selected critical section. Finding the temperature field of the piston involves solving the differential heat equation. According to the results of the calibration calculation estimates of the thermal and stress–strain state of the piston when the engine was forced to 4CH8,2/7,56 at the mean effective pressure, recommendations and restrictions were formulated.

The methods of loss in the flow parts of power plants (PP) of aircraft, gas-pumping units (GPU), gas turbine engines (GTE), and gas turbine plants (GTP) accounting are considered. A new method for approximating gas-dynamic characteristics and calculating the efficiency coefficients of the units including compressors and turbines optimizing their geometry and modes is proposed. To verify the method, the results of factory tests, 2D and 3D CAD/CAE-simulation of the flow and gas-dynamic characteristics of the flow part components, including blowing of the blade profile gratings were used. It is shown that this method can be effectively used to optimize the flow parts geometry and to select the modes of operation of input and output devices, blade rims as part of compressors and turbines, and transitional ducts between cascades. It is suggested to use the method to control the change in the characteristics of the GTE units during operation. This can significantly improve the accuracy of parametric diagnostic GTP and GTD. The proposed method can be used to monitor the state of aggregates and systems in the power engineering, in transport, and in other areas.

The dependence in the operator form for the shearing stress in nonstationary fluid friction is obtained. The transfer functions for the shearing stress of the velocity of the moving element and the pressure gradient are determined. Based on the analysis of amplitude-frequency characteristics, the boundaries of a quasi-stationary approach are established for calculating the forces of nonstationary viscous friction on the moving elements of hydraulic devices. To calculate the shearing stress, considering the effect of the inertia of the flow structure, we consider a nonstationary plane laminar motion of incompressible fluid in the gap between a moving and a fixed element in the Cartesian coordinate system. The solution of the equation of motion in partial derivatives is fulfilled using the Laplace transform. The estimation of the boundaries of the quasi-stationary approach to the calculation of the forces of nonstationary viscous friction is made from the amplitude-frequency characteristics of vibrations of the moving element and the pressure gradient. As the boundaries of quasi-stationarity, the frequencies at which the amplitude changes by more than 5% are adopted.

The relevance of studying the deformation and strength is related to the use of thin circular cylindrical shells in structures exposed to intense dynamic operation. When studying complex dynamics issues, emphasis is made on solving the problems of free oscillations in structural elements. Real shell structures will unavoidably deviate from a perfect cylindrical shape (the initial imperfections) that emerge either in production or in operation. It is known that such imperfections result in specific phenomena as shells oscillate. Splitting of the bending frequency spectrum occurs not only when the number of shaping waves equals that of the shell–shape imperfection waves, as is believed nowadays, but also when the number of shaping waves is half that of the shell-imperfection waves. In the first case, the greater split eigen-frequency equals the frequency of perfect-shape shell oscillations, while the lower frequency is below that. The paper presents studies of how the initial deviations from a perfect circular shape affect the dynamic eigen-parameters of a thin circular cylindrical shell. It discovers the emergence of new splitting zones of the imperfect-shell bending frequency spectrum.

The mathematical model which links an information signal with the parameters of technical state of mechanical node in the best way will allow developing methods for diagnosing emerging defects at the operational stage. Development of a mathematical model of spindle unit bearing assembly, which would analytically describe the mechanism of vibration signal formation, linking it to the parameters of the technical state, is a relevant objective at the present time. Perhaps, such a mathematical model will effectively apply the Huang–Hilbert transform to vibration signals, using adaptive decomposition of signals into physically significant components, and also improve the efficiency of currently used analysis methods. The obtained mathematical model qualitatively determines the mechanism of the frequency composition of the vibration spectrum appearing, takes into account the microgeometry of the raceway and ball profiles, when the radial (angular contact) ball bearing works, and gives a quantitative estimate, the error of which will largely depend on the signal/interference ratio of the experimentally obtained time implementation of vibration acceleration (vibration displacement).

A computer simulation of the open-top wagon along the track section adjacent to the rail joint is performed taking into account the ballast subsidence in the joint area. At the same time, a number of parameters influencing this process were varied. The range of dynamic forces values that arise between the wheel and the rail when passing the joint by a freight car at operational speeds is determined. The evaluation of stresses obtained as a result of solving the contact problem for the wheel and the rail by the finite element method is estimated. The problem was solved taking into account dynamic efforts found by computer simulation. The intensity of stresses and deformations is determined. The contact pressures in the elements of the rail joint are calculated using three-dimensional finite element models. Contact problems for two variants of the wheel arrangement are considered: above the edge of the joint and at a sufficient distance from it. Based on the results of the solution, an approximating relationship is proposed for the location of the wheel at the rail edge to determine the maximum contact pressure.

The authors of the article have developed a unified method for determining the forms and frequencies of free transverse vibrations of a direct rod of variable cross section, taking into account tensile forces caused by the rotation of the rod. The technique is based on finite element approximations where the rod is represented as a set of four-degree bendable elements. The Kirchhoff–Love hypothesis is used while calculating. To obtain the equations of motion of finite elements, the general dynamic equation is applied. The mass matrix, the physical stiffness matrix, and the geometrical stiffness matrix of the final element are obtained taking into account the linear law of variation of the linear mass, flexural rigidity, and tensile centrifugal force along the length of the element. To get the equations of free vibrations of a finite element rod model, the authors have used the general dynamic equation. They have carried out the approbation of the developed technique with the determination of several low natural forms and frequencies of transverse vibrations of a rod of variable thickness rotating around a fixed axis. To determine these forms and frequencies, the iteration method in the subspace is used. This method allows calculating the lower forms and frequencies of natural vibrations of nodes, units, and structures operating in the field of centrifugal forces. The described algorithm is implemented as a program in the MATLAB package.

Within the framework of ensuring availability at oil and gas processing facilities, an analysis of methods for assessing the reliability of a technical object based on the reliability, availability and maintainability of individual elements was made. The difficulties arising from the complex assessment of the reliability of complex technical objects using different methods are shown: A number of methods did not allow to assess the entire complexity of the object, and other methods led to an increase in the complexity of calculations with an increase in the number of individual elements. The authors propose to use combinations of previously known methods at different hierarchical levels for system analysis. An algorithm for assessing reliability based on dividing a complex object into elements, the evaluation of the reliability of which is determined by one of the most suitable methods, such as the Markov models of states and transitions or statistical models, has been developed. Additional designations are proposed for the unambiguous interpretation and structuring of the reliability assessment system. As an example, the calculation of the failure-free operation of the gas treatment unit of the tar visbreaker was made. The possibility of calculating complex interdependent systems, where linear statistical calculation methods are not applicable, and the labor intensity for the Markov method has power-law dependence, is shown.

Based on the analysis of various methods for modeling gas-dynamic processes, a methodology has been developed for calculating the main parameters in the launch canister, taking into account the heat exchange processes. The development of the technique includes the choice of physical and mathematical models of gas-dynamic processes in the launch canister, which allow obtaining a stable and convergent solution. The results of FLUENT software package numerical modeling of gas-dynamic processes in the launch canister have been presented, taking into account the heat exchange processes for the given parameters of the heat-shielding coating. The parameters of the MX missile are used as the main parameters for the calculation. Despite a slight increase in the exit time (4%) and the average volume pressure in the launch canister (4–6%), it has been obtained that the effect of heat transfer is increased over time, and for missiles of longer length, it will be more significant. Based on the results obtained, the value of the coefficient taking into account heat transfer was found, and its comparison with known experimental data was made. The obtained coefficient is used to improve the technique on the basis of finding the average volume characteristics in the launch canister. The use of the numerical simulation technique will allow further evaluation of the effect of changes in the parameters of the thermal protection coating and the parameters of the combustion products of the powder pressure accumulator on the dynamics of the missile movement in the canister.

As a research task, the authors determined an attempt to assess the possibility of applying the methods of vibroacoustic diagnostics to detecting an electrode breakage during electrical erosion processing (EDM). The presence of a diagnostic system allows timely replacing tools and thereby increasing the productivity of the process. During the review of previous research, considerable attention is paid to identifying the main parameters of EDM processing, among which the most important is gap size in the electrode gap. The absence of high-quality automatic control of this gap on the machine makes the EDM process ineffective. Experimental research was conducted on a wire-cut machine “CUT 1000”, the materials being processed were alloys VK 60, T15K6 and VOK60 (WC, TiC and ceramic alloys). The authors proposed a dynamic model of the erosion treatment zone and experimentally showed a change in its frequency characteristics with increasing concentration of erosion products. There was established that the measurement of amplitude-frequency characteristics allows detecting an increase in the concentration of erosion products and determining the moment of electrode breakage with a sufficiently high accuracy. The results of research of vibration signals in the processing of conductive ceramics were given. Monitoring was made directly in the process without removing the tool and the workpiece. The problems of processing conductive ceramics and possible ways to solve them by controlling high-frequency vibrations are shown.

The article describes the method of estimating the values of the pressure forces acting from the power plant when jacking tunnel linings in the microtunneling technology. The assessment carried out for the frictional component of the effort of punching in straight sections when the process is restarted after the punching stops of a certain duration. For the lining, pressed with the use of lubricating solutions, the time evolution of the effect of “sticking” in permeable rocks when the shutdown works is taken into account. This effect allows one to account for the observed increase in effort of pushing when it is restarted. The dependence of the pressure effort of the length of stoppage in time is given. In this relationship, the rate of increase of this area is defined by the time of dissipation of lubricant pressure on contact to initial pressure pore waters. Key parameters, thus, are the module of volume compression and the coefficient of soils permeability. The area of contact is directly proportional to differential pressure, a square of external lining diameter, and inversely proportional to amount of overcut and the module of volume compression of the soil. Resisting force is defined by the areas of contact soil—lining and a lubricant-lining, and shear strengths on these contacts. The received dependence allows considering observable increase in thrust forces at jacking restart after stoppages. New physically well-founded dependences for increase of thrust forces are resulted at duration increase of stoppages. The comparison with experimental data has allowed defining the parameters entering into these dependences.

Despite significant achievements in the diesel engines starting characteristics improvement, there are still problems associated with unstable ignition, poor combustion of fuel during start-up and subsequent warm-up. For the conditions of a diesel engine’s cold start, the characteristics of the fuel burnout, heat generation, and thermal management are determined. The inaccuracy in the cylinder pressure measuring was calculated. The patterns of fuel burnup, obtained on the basis of the experimental pressure diagrams analysis, make it possible to obtain a good agreement between the calculated and experimental results. The influence of the start-up conditions, including the increase in the intake air temperature, on the magnitude of the kinetic indicators of combustion characteristics and the completeness of combustion of fuel is established.

The finite element method (FEM) which is popular in calculating strength of engineering constructions disposes a long list of basic finite elements (FEs) for building discrete finite element design dynamic models (DDMs) of lifting cranes. The paper presents the general methods of developing equations of motion for crane systems with multiple (n) degrees of freedom and their components in the form of matrixes of stiffness and masses of a thin-walled bar and plate FEs, the latter being analyzed using the Kirchhoff plate theory. The produced final formulas help to analyze the quality of DDM of structural steelworks of the bridge cranes built using bar FEs with a closed profile and plate FEs based on the comparison of general bending stiffness of longitudinal girders and on the comparison of fundamental frequencies (FFs) and eigenforms (EFs) of oscillations of their DDM.

The article is dedicated to the study of anti-vibration properties of vehicle suspension at optimal instantaneous damping control in oscillation cycle. These suspensions in foreign literature are called “semi-active control suspensions.” However, its vibration isolation properties have not been thoroughly analyzed. This article presents ineffective damper zones in the oscillation cycle, mathematical models of vehicle suspension, and the results of theoretical and experimental study of vibration isolation properties of one- and two-mass oscillation systems simulating a suspension at optimal instantaneous damping control in the oscillation cycle. The results in the form of amplitude-frequency characteristics of sprung and unsprung masses displacement and accelerations, waveforms of resonant oscillations and elastic-damping characteristics of oscillation systems at resonance proved that optimal instantaneous damping control does not improve vibration isolation properties in response to shocks and noise in the suspension, thus setting a problem of searching and studying the ways of a smooth damping change in the oscillation cycle.

The change in the technical condition of internal combustion engines in operating such systems as the feed system, ignition system, cylinder-piston group, and intake and exhaust system leads to the deterioration of the combustion process, the growth of toxic components and, as a consequence, the acceleration of the catalyst resource exhaustion. Accordingly, a catalyst failure will lead to a noncompliance of the vehicle’s emission standard with the applicable EURO standards, the subsequent replacement of which will not change the situation. It will be necessary to replace some system elements to eliminate the root causes of the catalyst failure. In this regard, when operating ICEs, it is vital to develop ways to control the time history of the concentration of toxic components of CO, CH, CO2, and O2 in exhaust gases. It is possible when portable gas analyzers built into the exhaust system are used. The operation of the portable gas analyzer can be organized discretely, in the form of test modes for monitoring the toxicity parameters, for example, at idle speed, in the acceleration mode, in constant power and load conditions, when individual engine cylinders operate selectively. In this study, the cylinders are completely or partially deactivated by the developed portable device—gasoline engine loader. Considering a high selectivity of the load impact on individual cylinders and its significant variation, the catalyst failure can be prevented, including due to the adaptability of the actuating elements to the change in the technical condition of separate unit.

Numerous factors affect the quality of soil cultivation. The modeling of the cultivation-affecting processes requires considering the parameters of the implement as well as those of the machine with a transfer link. The research team has found the stable region of torsional vibrations for tractors and cultivators. The implement drive is considered to be a single-mass dynamic system engaged in torsional vibrations. The moment of inertia and the system rotation angle is applied to the tiller axis. The paper presents a differential equation of torsional vibrations written in the operator form and in the characteristic form to study the effects of process parameters on the elasto-dissipative characteristic of the drive. The condition of ensuring stable torsional vibrations and zero self-oscillations in the drive has been defined.

The design of injector nozzles providing improvement of the fuel injection and atomization processes quality in diesel engines is suggested. This is achieved by making grooves on the injector nozzle, each of which forms an expansion of the output channel of the corresponding spray hole. Experiments have been carried out for the D-245.12S diesel engine, alternately equipped with experimental and serial injector nozzles, and operated on diesel fuel, and on 80% diesel fuel and 20% rapeseed oil mixture. The possibility is demonstrated in terms of improving the exhaust gases toxic characteristics using the diesel engine equipped with the experimental injector nozzles and operated on 80% diesel fuel and 20% rapeseed oil mixture. The combination of the experimental nozzles and composite biofuel, containing 80% of diesel fuel and 20% of rapeseed oil, resulted in lower emissions of nitrogen oxides by 8.1%, of carbon monoxide—by 12.4%, and of unburned hydrocarbons—by 15.9%.

It is known that when an elastic wheel, e.g., a car tire, moves on a solid supporting surface, its normal reaction is displaced longitudinally. The direction of such displacement in relation to the forward speed vector of the wheel depends on the wheel movement. The magnitude of such displacement (drift) is important as it determines the center of the friction-at-rest area in the contact spot, which triggers a lateral reaction of the supporting surface that determines the stability of wheel and car movement to a great extent. There used to be known only two components of such a drift. The first component characterizes hysteresis losses (radial and tangential) due to the wheel rolling. The second component characterizes the longitudinal elastic displacement of the wheel axis in relation to the geometric center of the contact spot. The authors have experimentally identified a new, i.e., the third component that characterizes elastic angular deformations in the tire, which cause the curve of normal stresses in the contact spot to be asymmetric. This third component has been found to have much greater magnitude than the two other components.

An expression is suggested for determining the coefficient of the oxygen reaction activity K1 when modeling the process of fuel combustion in the compression-ignition engine. Using coefficient K1 allows modeling the decrease in the rate of combustible mixture combustion due to the inert components in case of the changes in mixture composition caused by combustion and exhaust gases recirculation (EGR). The numerical research has been performed for the process of combustion of the homogeneous mixture of air and dimethyl ether in the constant volume chamber. The increase in the inert components content in the combustible mixture in case of the EGR (increase of the residual gases coefficient from 0 up to 0.5) results in the slowdown of the dimethyl ether combustion process, decrease in the maximum combustion rate and postponed achieving of this rate. The maximum calculated combustion rate without consideration of the inert components decreases by 23.8%. Taking into account the inert components, it decreases 2.52 times by using coefficient K1. In the first case, the maximum combustion pressure decreases only by 0.3 MPa and is registered 0.04 ms later. In the second case, the maximum combustion pressure decreases by 0.46 MPa and is registered 0.41 ms later, though the initial amount of oxygen decreases identically—1.86 times. The main causes of the slowdown of the dimethyl ether combustion in conditions under study are the decrease in the initial amount of the oxygen molecules and the 1.53 times decrease in the reaction activity of oxygen.

The chapter presents a brief description of the experimental unit made on the basis of a dynamic test bench and the results of bench tests of a single-support pneumatic suspension, including sprung and unsprung masses, pneumatic spring with a sleeve-type rubber-cord casing, air damper mounted in the piston of the air spring, receiver and hydraulic shock absorber. The chapter contains the following: elastic characteristics of air springs with different operating volumes, damping characteristics of the hydraulic shock absorber, oscillograms of free damped oscillations of the sprung mass of 0.5 t after the push of the suspension from the bottom up and down by 100 mm, amplitude-frequency characteristics of oscillations of the sprung and unsprung masses at a harmonic kinematic disturbance with an amplitude of 12 mm. The maximum temperature and the time of reaching the steady-state temperature of the various surfaces of the air spring are determined with the help of a permanently installed professional thermal imaging camera.

The article discusses the trunnion of a ball mill in the framework of the theory of elasticity, which is subjected to uneven thermal effects due to the heating load. Long-term operation of the mills leads to a significant wear of mainly mechanical parts of the supporting rotating parts—pins. There are various defects on the working surface of the trunnion, which, under the action of dynamic loads, contributes to the loss of working capacity and long downtime during repair. The study of the stress-strain state will determine the parameters for restoring the cylindrical surface of the trunnion. The equations describing the radial displacement of a point inside the trunnion of a ball mill are obtained. The equations describing the movement of the trunnion points of the ball mill are derived. The stress-strain state of the trunnion of the ball mill was determined depending on the temperature of the inner and outer surfaces of the trunnion. Deformations and stresses arising on the surface of a pin are investigated by numerical methods.

The influence of the stiffness of the rear leaf spring on the vibration loading of the van is estimated using a spatial model of its dynamic. The new model of spatial oscillations of the van with all-metal body taking into account the dynamics of the movement by road microprofile, nonlinearities of dynamic hysteresis characteristics of elements of the vibroprotective systems and tires, taking into account the deformation of frame and body, is built. The calculations were carried out when moving the van in two weight states: empty and full weight. For analysis of the vibration loading of the van, the spectrums of vertical accelerations at several points of the van construction were obtained. All calculations were performed in the “FRUND” programmatic system. Based on the calculation results, the rational stiffness parameters of the rear spring are proposed. The results obtained in the course of calculations were constructively realized by removing the fourth and sixth leaves from the standard leaf rear spring. This also led to a significant reduction in the weight of the rear leaf spring.

The hydroelastic bending oscillations of a three-layered wall of narrow parallel-plate channel with viscous flow were studied. We analyze the hydroelastic problem of a plane type and consider the upper channel wall as a rigid vibrating stamp and the bottom channel wall as a three-layered beam resting on elastic foundation. The flow in the channel is studied within the viscous incompressible fluid model. We investigate flow as a creeping one and assume a Winkler model for elastic foundation. The three-layered beam is a sandwich construction, which consists of outer layers and a stiff lightweight core, as well as three-layered beam kinematics is described by using the postulate of broken normal. The mathematical model of the investigated parallel-plate channel consists of dynamic equations of the three-layered beam with stiff lightweight-core, dynamic equations of the creeping flow and boundary conditions. We assume boundary conditions at the channel walls are no-slip ones, as well as boundary conditions at the channel edges are pressure difference. We studied the stationary oscillation problem under loading harmonic vibrating stamp. The analytical solution of the considered problem was obtained. We suggest the frequency-dependent function of three-layered beam deflection distribution along the channel and make calculations of the channel wall amplitude-frequency response.

The paper is devoted to the problem of reduction of the vibration level of pipelines, caused by resonance with the disturbing frequency of pumping units. Each case of the occurrence of pipeline vibrations requires a careful and qualified analysis, because no universal methods for reducing the vibration of technological pipelines have been developed. It is offered to use vibration isolators based on the special shaped with negative stiffness area for vibration isolation. A pipeline in this case acts as a stabilizer for a vibration isolator with negative stiffness. The combination of these two elements in a particular area force characteristic “pipeline—vibration isolator” system becomes flat, thereby providing a reduction of its stiffness and thus natural frequencies. Analytical calculations have been made to prove the effectiveness of the proposed solution. Thus, in the case considered in the paper, the natural frequency of the pipeline oscillations is reduced from 33.33 to 9.5 Hz. A passive vibration isolator based on an elastic element moving along the guides of the design form perpendicular to their axis allows creating the force characteristics of a given shape that are necessary for vibration protection in each case.

In this paper, a Jeffcott model with an offset disk rotor system with two cracks has been analyzed. By using the theory of fracture mechanics for two cracks in a Jeffcott model, a mathematical model of the rotor shafts with cracks with changing the crack depths has been created. The increase in the growth of the cracks is one of the most dangerous phenomena in rotors. The effect of changing speeds on the dynamic parameters of journal bearings (stiffness and damping) and then on Sommerfeld number has been studied. The relation of the types of stiffnesses ratios of a cracked rotor and stress concentration factor of the crack tip, with the angle of rotation rotor, has been found. The results have been obtained analytically using MATLAB. The results show that when cracks are fully open, the stiffness ratio in all directions reaches to a minimum while the concentration stress reaches to the maximum.

The relevance of studying the deformation and strength is related to the use of thin circular cylindrical shells in structures exposed to intense dynamic operation. When studying complex dynamics issues, the emphasis is made on solving the problems of free oscillations in structural elements. Real shell structures will unavoidably deviate from a perfect cylindrical shape (the initial imperfections) that emerge either in production or in operation. It is known that such imperfections result in specific phenomena as shells oscillate. This paper dwells upon the bending oscillations in thin shells. It demonstrates there may emerge an additional bending frequency spectrum-splitting zone due to the initial shell-shape imperfections. It has been discovered that the bending frequency spectrum splitting occurs not only when the number of circumferential dynamic strain waves equals that of the shell-shape imperfection waves, as is believed nowadays, but also when the number of shaping waves is half that of the shell-shape imperfection waves.

The article presents a test hydromechanical test bench, methods, and results of testing petal gas-dynamic bearings when the position of the rotor axis of rotation changes in space. A mathematical model of the rotor dynamics in a petal bearing is proposed based on a modified Reynolds equation in a non-stationary formulation for a viscous compressible fluid. The solution of the specified equation allows finding reactions of a lubricating layer. The reactions of the lubricant layer allow us to find the stiffness and damping coefficients necessary to record the equations of motion. The case of a rotor displacement in the vertical direction is considered, and the adaptive behavior of the rotor in a petal gas-dynamic bearing is shown. The principal hydraulic scheme and the description of the test bench operation are presented. The test bench simulates external influences in a wide range. The functional scheme of the information-measuring system is given. The article proposed an interface for interconnection of the operator and the information system. In addition, it provides some graphs of the oscillations of the rotor y-axis during the motion of hydraulic cylinders in the vertical direction.

It means that all gas well parameters such as pressure, temperature and gas flow decrease. As a result of all these factors influence, there is a liquid accumulation which occurs in the wells and gas-collecting system (GCS) pipelines. That is why GCS pressure loss increases, and ice and hydrate plugs’ formation risk increases too. There are many methods used to remove liquid. In fact, the most useful ways are a well, flowline, and gas gathering line header blowdown. But it leads to significant gas loss and field environmental degradation. It is offered in this paper to use low-pressure gas line to blow down. The low pressure is made by low power compression unit. The low-pressure gas feeds through this line to the complex gas treatment plants. Designed automated instrumentation and control system allow one to use existing temperature and pressure-measuring means. We also offer to use existing equipment which was earlier decommissioned because of falling production. Conducted research on the offered blowdown methods and control system showed their efficiency.

The content of the antioxidant additive ionol in mineral transformer oil within the limits of normalized values (0.08–0.40 wt%) provides reliable operation of oil-filled high-voltage electrical equipment. One of the methods of an inhibitor concentration control in a liquid dielectric is gas-liquid chromatography. However, in the option offered by certified methods based on gas chromatography, it is impossible to ensure high accuracy in determining the amount of inhibitor. In order to reduce the analysis processing time, as well as to increase the reliability of the measured concentration of ionol in a complex hydrocarbon matrix of oil, a new method of chromatography mode using the distribution coefficient of ionol in the oil–ionol-solvent system is proposed in this article. In Russia, the most widely used brands of mineral insulating oil are such as GK, TKp, Nytro 10XN, Nytro 11GX, and T-750. The value of the distribution coefficient for the listed brands of oils differs from each other (from 2.30 to 2.61), which indicates the unevenness of the distribution of ionol between the molecules of carbohydrates of different chemical compositions and, in general, because of the chemical composition of various brands of oils.

The article proposes a concept of utilizing steam, gas, and wind energy techniques to improve existing autonomous energy and water supply systems by adding new resource-saving multifunctional heat, electric power, cold, and water generating apparatus. The proposed apparatus is fueled by hydrogen produced in its wind energy unit, thus reducing the rate of consumed hydrocarbon fuel, while thermal decontamination of industrial and utility wastewater helps in improving environmental safety of the facility. The article contains a schematic for such apparatus as well as several equipment variations for energy and water supply systems with preset parameters such as electric and heat energy loads and amount of cold and wastewater produced. The proposed set of parameters allows evaluating production, technological, and economic efficiency of the apparatus by considering various interrelations between production facilities and external energy and water supply sources. The comparative analysis of existing energy and water supply systems with autonomous energy and water supply units that utilize the proposed multifunctional apparatus has shown that its installation at various production facilities improved production, technological, and economic efficiency of such facilities.

In this paper, the results of the ladle–tundish system were studied for the timely slag cut-off during steel casting. Accelerometers were installed to provide the access of the protective tube to the manipulator of the steel ladle and the body of the tundish. The search for regularities of the vibration acceleration signal was carried out in order to determine the state, which precedes the beginning of the slag flow from the steel ladle to the tundish. The filtering methods (Chebyshev filter), spectral, and wavelet analysis were applied for the signal processing. This fact can be seen in the Fourier and wavelet spectra of transformations at certain frequencies. The signal itself is quite noisy with the vibrations of the workshop; it is not possible to analyze the signal only using the amplitude. In this paper, a basic algorithm for the diagnostics of the beginning of the slag flow has been developed focusing on the effect of the vibration level reduction in the spectra of the vibration acceleration signal. To implement the algorithm, a Fourier transformation was performed for the signal from the manipulator of the protective tube, and the wavelet transformation was carried out for the signal from the surface of the tundish, and then the signal was integrated in the frequencies defined by the study and the moving average filter was applied.

This research aims to study the arrest of crack propagation in oil or gas steel pipelines by using circumferential ribs as arresters. The use of ribs is much cheaper than high-grade steel with high fracture toughness. It has been shown that two ribs per pipe could prevent the most dangerous type of the pipeline fracture, which is a large length longitudinal crack. In this paper, two types of simplified estimations were used: the first is by calculations of stress intensity factors (KI) and the second is by analysis of perfectly viscous (plastic) fracture. Both estimations were done on a pipe with plane wall and a pipe with ribs. The results showed that the sizes of ribs that can be technologically obtained increase the resistance of pipes to cracking by 30–50% and could be useful in preventing longitudinal crack propagation. Experimental verification of the results obtained on small-scale models has shown that there are some difficulties that can make direct transfer of results from small-scale model to full-scale structure impossible, and these difficulties are also discussed in this paper.

The article presents a solution to the problem of improving the operational characteristics of agricultural machinery aggregates by applying a monomolecular protective film on the surface of tribounits. In accordance with the strategy for the development of agriculture, one of the priority areas of which is import substitution, an analysis has been made of existing methods for improving the performance of agricultural machinery aggregates by modifying the interface surfaces with surface-active substances (surfactants). The article presents the theoretical justification and the results of the experiment, confirming the rationale for increasing the operational wear resistance of gears and life by changing the magnitude of the friction on the interface surfaces. The properties of molecules of surface-active substances are used to change the surface energy at the interface and thereby affect the physicochemical processes: wetting, wear, friction, corrosion (Gaidar et al. in Increasing wear resistance of friction units, Works of GOSNITI, pp 40–47, 2016 [1]; Volkov et al. in Improving the tribological properties of lubricants based on gear oil, innovative directions of development of technologies and technical means of agricultural mechanization: materials of the international scientific-practical conference dedicated to the 100th anniversary of the Department of Agricultural Machines of the faculty of Agricultural Engineering of the Voronezh State Agrarian University named after Emperor Peter I, pp 115–119, 2015 [2]; Karelina et al. in Improving the tribological characteristics of lubricating compositions based on gear oil, innovative technologies and technical means in the agricultural sector: materials of the international scientific-practical conference of young scientists and specialists, pp 228–233, 2015 [3]; Gaidar and Karelina in Fluorine-surfactant adsorption and its effect on the lubrication of friction in the conditions of boundary and hydrodynamic friction, from nanostructures, nanomaterials and nanotechnologies to nanoindustry, pp 44–45, 2015 [4]). The methods of forming a monomolecular protective film are presented as well as the technology of modifying the surfaces of friction pairs by surfactants is optimized, based on a model of the behavior of a drop on the surface and an estimate of the wetting angle. The results of experimental studies of the effectiveness of the modifier, evaluation of its physicochemical and operational properties are presented.

When improving the design of electronic control devices and car stability control system algorithms based on maximizing the road–tire friction coefficients, one has to evaluate the friction between the elastic wheel and the bearing surface. $$\varphi{-}s_{x}$$-diagrams are simulated to that end. These are the dependencies of the friction coefficients on the wheel sliding. What they look like depends, aside from external conditions (type of coating, lateral forces, etc.), on the law of contact-patch sliding increase, which in its turn depends on multiple factors including the estimated radius of the wheel. As of today, free radius, dynamic radius, and rolling radius values are used to that end. In this case, the difference between them can reach up to 20%, depending on the value of the tire radial deformation. Despite the large number of studies on the theory of rolling wheels, experts still have not developed a consensus on what radius should be used for these purposes, which, naturally, is accompanied by a difference in the calculations in which these radii are used. The researchers prove the advantages of using the estimated kinematic radius and propose a correlation for calculating it. Herein are presented $$\varphi{-}s_{x}$$-diagrams for different radii.

Most researchers attribute the failure of bearings of a cranked shaft of the engine with the violation of hydrodynamic lubrication. Under normal engine operating conditions, the main oil line maintains the pressure required to ensure optimal lubrication of the friction surfaces. As the bearings of the crankshaft wear out and, consequently, increase the gaps in them, the flow of oil through the bearings is facilitated; in this regard, the pressure in the oil line decreases. The pressure and oil flow through the connecting rod bearings are due to a large number of factors: the performance of the oil pump, the operating mode of the engine, and the degree of wear, as well as design features of lubrication systems, individual components and parts, the method of supplying oil to them. In addition, the oil flows in the rotating crankshaft are subject to centrifugal forces, resulting in pressure loss in the channels up to 50% of the nominal value, which leads to a decrease in oil flow through the connecting rod bearings. Negatively affect the modes of rupture of the oil flow supplied to the connecting rod cavity, which actually precede the failure of the crankshaft bearings. Their research is devoted to this work.

In the article, investigations of antifriction films formation at friction in dioctyl sebacate (DOS) medium with additives of cholesteryl esters of caproic and oleic acids. The relevance of the study is due to the development of biodegradable lubricants. The time required to achieve a friction coefficient of 0.02 in DOS medium occurs after 20,000 s from the start of the test, in DOS with 3% LCKA medium after 13,000 s, and DOS with 3% LCOA medium after 1000 s. The elemental analysis of antifriction films showed that the films contain organic and inorganic components. The organic part consists of dioctyl sebacate molecules. The inorganic part includes iron compounds. Cholesteryl esters are capable of planar orientation on friction surfaces and form layered structures in the zone of tribocontact. This provides an additional reduction in the friction coefficient and an increase in the energy-saving properties of the lubricant. This effect is achieved due to the realization in the friction zone of the mesomorphic state of a lubricant, which is characterized by an ordered oriented arrangement of the molecules of the mesogenic additive.

The mandrel taper errors connected with its manufacture may be added by the operation errors emerging as a result of wearing out caused by friction in the mating conical surfaces. Depending on the ratio of deviations from parallelism and alignment of mandrel taper and spindle socket and their directions, the initial tool carrier contact may occur at the point of a large spindle socket diameter (intensive wearing out of the mandrel taper bottom part and the spindle socket) or at the point of a small diameter of the mandrel taper (intensive wearing out of the upper part of the mandrel taper and the spindle socket). The formation of the friction path will depend on the initial contact of the mandrel taper and the spindle socket. The result of the study includes obtaining dependencies that allow determining the areas of intense wearing out and contacting pressures when using the automatic tool changer system, depending on the deviations of the mandrel axes and the spindle socket from alignment and parallelism at the moment of initial contact determined by the auto operator’s work errors.

It has been established that with the same initial data of deviations of the covered and spanning surfaces of a hydraulic sliding bearing, the value of the calculated diametral clearance depends, in general, on the law of the distribution of errors. It is not always possible to guarantee the fulfillment of these errors, as a result of which destabilization of the gaps of the multi-support shaft support nodes is characterized by the relation $$h_{1\hbox{min} } \ne h_{2\hbox{min} } \ne h_{3\hbox{min} } \ne h_{4\hbox{min} }$$. To calculate the diametrical gaps in a cylindrical hydraulic sliding bearing, a model was proposed based on the condition that the circumscribed and enveloping surfaces are made on the limiting dimensions that can be combined in an unfavorable and favorable direction of contact pairing. The obtained values of the volume of worn material with both options, showing the possibility of using automated calculation in the software tool COMPAS-3D.

A method for the computation of the lubricating fluid circulation is presented. It uses orthogonal meshes of the inner volume of assemblies and a particle-in-cell method to calculate the flows of lubricant. The lubricating fluid volume consists of a set of particles which can move without interaction in the field of a force of gravity. Particles are sprayed from special areas, move in the inner volume and drain on the border of a volume. Particle movement on the inner surface of a model is calculated using the particle velocity, damping coefficient and normal to this surface. CAD geometry of assemblies is used to generate a mesh of inner volume. The result of calculations can be presented as the movement trajectories of particles or as the accumulation of particles on the border. The charts of movement and velocity of particles can be generated. The program system, which uses this method, is developed. Testing on test samples is performed. The calculation of the circulation of lubricating fluid in the reducer of a cargo vehicle is carried out. Directions of further development are given.

Electric machines are widely used in the assembly, and mechanisms of modern equipment and devices operate in different climatic conditions. These conditions often determine the peculiarities of operation of electric machines, repair and preventive measures. In many ways, the reliability of DC electric machines is determined by the node of a sliding current collector (UST), in which the current-carrying brushes are in dynamic and static contact with the plates of the metal collector or ring. Physical, mechanical, and chemical processes occurring at the interface of the contacting counterbody data determine the switching processes and reliability (UST). The purpose of the article is to analyze and study the impact of probable physical and chemical factors on the operational reliability of the sliding current collector unit of electric machines. The results of scientific and practical work allow determining the measures aimed at eliminating the negative impact of adverse physical and chemical environmental factors on electric machines.

Thrust bearing is one of the main parts of a submersible electric motor and its service life to a large extent determines the reliability of the entire water pump system. However, the problem of thrust bearing service life in submersible electric motors has not been studied appropriately. In this article, an expression, which allows one to estimate the service life of thrust bearing in submersible electric motor through the initial rate and the acceleration of its wear, has been obtained. The results of the bench-scale tests referred to studying the rate of thrust bearing wear depending on operational factors are presented. Bench-scale tests were based on the experimental design theory. The variation levels of operational factors were determined during the experimental studies on the basis of monitoring water supply wells in the Urals Federal District. To reduce the number of experiments, a fractional factorial experiment with threefold replication has been implemented. It has been revealed that the presence of mechanical impurities in water and water hardness have the greatest effect on the wear rate. It has been shown how to find the initial rate and the acceleration of thrust bearing wear, which determine its service life, on the basis of the experimental dependences of the thrust bearing wear rate on the operational factors with two different operating times of a submersible electric motor. The article will be useful for employees of enterprises engaged in repairing submersible electric motors, as well as for companies involved in operation and maintenance of water pumping units.

A systematic investigation of fracture features of structurally and crystallographically textured billets in a two-phase Ti-6A1-IV-IMo alloy impact and low-cycle tested with a light metallographic, X-ray, and scanning electron microscopy was carried out. It is indicated that a reduction of the tensile properties is induced by the structurally and crystallographically precipitated fields of basis orientation of the interface boundaries of 20–30 µm in width spaced across the thickness billet by 100–170 µm. They are responsible for increasing the anisotropy of shock values and increasing the scattering of the results of low-cycle tests of samples in two-phase titanium alloys. The lower the applied stress value at the time of the specimen testing (impact or cyclic), the more the contribution of crack initiation period in its life time, the more important is the account of the number and geometry of the location in a bulk of the flat billets of such structurally and crystallographically pronounced fields effecting on the fracture mechanism change of the tested samples.

The purpose of this paper is to develop a new method, procedure, and measuring system for the identification of friction losses and mechanical characteristics of an asynchronous motor chain drive, as well as to apply them in the study of the impact of its design parameters and other operating factors on its performance. The proposed method allows monitoring the efficiency of a chain drive with a higher accuracy compared to existing methods since it does not require the use of strain gauges and, therefore, eliminates the need for their calibration and allows studying chain transmissions in dynamic operating modes in a wide range of rotational speeds and loads. The results obtained in the experimental part of this paper determine the factors that to a considerable degree affect the efficiency of a chain drive with a single-row sleeve-type chain, which indicates the applicability of the developed procedure and the measuring system for the control of its technical state under different operating conditions.

On the basis of personal inventions and well-known experimental research, the authors proved the characteristic of lubricant filling in the form of microscopic rounds as an antiwear and antifriction additive agent to improve toothed gearing quality. Trying to solve existing technical and economic contradiction, they proposed principally new construction of fixed members with higher kinematic pairs that notably increased wearability of fixed members working surfaces. The discrete contact is proved in the work, so that there is no need to apply special technology to make new gear wheels. Theoretical basis of storability of system-balanced condition on fixed members with higher kinematic pairs is elaborated. The main characteristics for the estimation of quality factors of reciprocating motion fixed member are defined: motion trajectory of the surface plate; ratio of recentering force to vertical load, i.e., rollback angle tg; angle between resultant of forces and its normal projection in the contact points, i.e., meshing angle. In static and dynamic bench tests of the fixed members, estimated characteristics were proved.

Friction conical conjunctions are considered in the present paper. The physico-mathematical model of dynamic contact interaction under conditions of static friction was taken into account for calculating the axial and diametrical tension of the frictional conical conjunction, taking into account displacements in the contact. The patterns of change in contact compliance in the normal and tangential directions, diametral and axial tightness in the conjunctions of conical contacts have been identified. A numerical–analytical method has been developed for the calculation of frictional conical conjunction, which makes it possible to take into account the contact compliance of the mating parts when designing and calculating. With the help of this method, the calculation of frictional conical conjunctions is made taking into account contact compliance. The results of the calculations were compared with the result of engineering calculations. Based on the comparison, the evaluation of the effect of contact deformations in the conjugation of the conical connection was made. It has been established that the consideration of contact deformations in the calculation of frictional conical conjunctions entails a decrease in the axial tension value by 20% and in some cases by 30%. The application program is developed and the certificate is received. The program allows you to perform a refined calculation of the static and dynamic characteristics of the elastic mechanical contact when designing frictional conical conjunctions. As a result of experiments, confirmation of theoretical calculations was obtained. Recommendations for making design changes have been provided.

The state of engine oil flow in hydrodynamic couplings is determined not only by geometrical or thermo-mechanical parameters of the interacting friction surfaces, but also by the flow regime. Due to heavy operating conditions of plain bearings in some regimes, self-organization processes on friction surfaces are inefficient. This negatively affects the continuity and damage resistance of forming lubricants. The regime of lubricant flow against the friction surfaces changes during operation. The engine oil flow frequently makes a transition from a laminar flow to a turbulent state. The article reports the results of evaluating possible operating regimes and conditions which enable the engine oil flow in the plain bearing of the turbocharger shaft makes a transition to turbulence. This allowed us to determine the thicknesses of likely boundary layers about the radius of surface roughness and compare them with the total thickness of the possible lubricating layer in a journal-bushing coupling. The proposed approach makes it possible to evaluate the overall state of the oil flow from the point of view of its layer pattern and the motion pattern of its components, which is necessary to improve the methods for ensuring reliability of lubricating the bearing of a particular turbocharger.

The results of the study of thermo-oxidative stability of mineral and synthetic motor oils in the temperature range from 170 to 200 ℃ are presented. The indicators of thermo-oxidative resistance are proposed, taking into account optical density, evaporation, and kinematic viscosity. It should be noted that, as an indicator of thermo-oxidative resistance, three variants of a combination of optical density, evaporation coefficients, and relative viscosity were considered. The effect of temperature on the oxidation processes was investigated, and an analytical relationship between optical density, evaporation, and kinematic viscosity was obtained. It is established that the oxidation of mineral oil produces two types of products regardless of the oxidation temperature, which is confirmed by the presence of a branch of dependence with a high rate of change in optical density. It has been established that the change in kinematic viscosity during the oxidation of mineral and synthetic oils occurs according to a general U-shape, regardless of temperature.

The complex method for evaluating the lubricating properties of technological lubricants and stresses when drawing axisymmetric products from sheet steel has been presented. To determine the friction coefficients in friction units during deep drawing the end-face friction, a test machine has been used simulating the contact coupling of friction units during the sheet steel drawing. Determination of the friction coefficients of friction units has been carried out when they were lubricated with technological lubricant RE-18 that contains fractal structures with copper, bronze, and zinc nanopowders adsorbed on these structures. The evaluation of the effectiveness of technological lubricants SL-2M, technical castor oil, and RE-18 during the sheet steel drawing has been performed on a modernized machine for testing the technological properties of sheet metal MTS-10H-1. The effectiveness of lubricants has been evaluated according to the proposed criteria: the force corresponding to the yield strength of the sample material; the maximum tensile force of the sample; the average diameter of the flange after drawing; the coefficient of ultimate strain; the difference between the diameters of the billet and the flange; the coefficient of relative ultimate strain; the drawing depth; the relative drawing depth. The determination of stresses in sheet materials is made using the model of sheet steel drawing in the ANSYS Workbench universal software system for finite element analysis.

Design improvement of motor-and-tractor internal combustion engines is aimed at differentiating the operating parameters of the lubrication system depending on the change in the operating modes and conditions, which increase in the precision of parts manufacturing, reduction of difference tolerances of operating process parameters and use of microprocessor control systems. Up to 20% of engine failures are failures connected with the wear of crankshaft friction bearings. Their known diagnostic methods have significant drawbacks: the need to take the engine out of operation, large time expenditures for diagnostics, impossibility of in-place determining the technical status of some elements. Today, the automotive industry is significantly ahead of the production of diagnostic tools. There appear concepts and models of machines, for which it is not enough to use low-sensitive pressure sensors. For such models, it is recommended to control pressure pulsations in the ICE oil line to determine the technical status and lifetime of internal combustion engines. When monitoring the technical status of main bearings, the diagnostics is performed at the crankshaft speed n = 880 , min−1, when using the complex for diagnosing crank-and-rod mechanisms and mechanisms of the lubrication system. The diagnostic parameter is the difference of minimum pressure amplitudes when the bearing operates through a cycle, with and without load.

The thermal state of the sliding bearings has a great influence in calculating the dynamics of the flexible rotor of the turbo-compressor. Experimental studies have shown that the temperature difference between the turbine and compressor bearings can reach twenty degrees. In addition, the temperature is unevenly distributed across the lubricating layer. It increases in the area of elevated pressure. The task of assessing the thermal state of the rotor plain bearings is relevant. The effect of eccentricity on the pressure distribution in a thin lubricating layer of a non-Newtonian fluid was considered. The distribution of temperatures and pressures in the lubricant layer was constructed taking into account the rheological properties of the lubricant. The boundary conditions that were used to solve the problem were taken from the experiment. The results will be used to solve the problem of the dynamics of the turbocharger rotor.

The issues of ensuring the tightness of sealing joints are considered. It is indicated that to calculate the tightness at the design stage, it is necessary to know the regime of the outflow of the medium being sealed, which is determined by the Reynolds number. It is shown that the Reynolds number is determined by the ratio of the linear mass flow rate through the sealing joint to the dynamic viscosity of the sealed medium. Dependencies of the relative contact area, the density of gaps in the joint, and the probability of medium flow from the dimensionless force elastic-geometric parameter fq should be determined taking into account the mutual influence of asperities of the rough surface. Said contact characteristics determine the functional of the permeability Cu which characterizes the sealing capacity of the sealing joint. Their role in various periods of loading of a sealing joint by a dimensionless load is shown.

On the basis of a simplified rigid model of a layered elastic body, an engineering technique for determining the parameters of a contact is proposed for the indentation of a spherical indenter into it. The model is based on the dependence of the displacement of the points of the half-space along the axis of symmetry on the magnitude of the applied distributed load. The reduced elasticity modulus and the Poisson’s ratio are determined depending on the elastic properties of the base and coating materials, the thickness of the coating, and the radius of the contact area. Equations are given for determining the parameters of a contact when a spherical indenter is indented into a layered body. The obtained results are compared with the exact solution of the spatial axisymmetric problem for describing the stress-strain state in an elastic layer when a spherical indenter is indented into it, obtained by A. P. Makushkin using the Fourier–Bessel integral transformation method.

The article presents the research results of effect of oxidation products on anti-wear properties, including the absorption coefficient of the light flux, evaporation, viscosity, the amount of wear, the coefficient of thermal stress, and the coefficient of resistance to oxidation. The method of research for lubricating oils for thermo-oxidative stability, determining the diameter of a wear spot and the effect of oxidation products on the anti-wear properties of the oils under study are described using test and control tools such as a device for thermal oxidation of oils, a photometer for direct electrophoretic oxidized oils, three-ball friction machine, and electronic scales. The dependences of the light flux absorption coefficient, volatility, and viscosity on the test time were constructed, by which the dominant influence of oxidation products was determined and then the amount of converted thermal energy and the thermal stress coefficient were determined. The article proposes to determine the quality of the lubricant from the graphical dependences of the thermal stress coefficient on the light absorption coefficient. According to the dependences of the change in the anti-wear properties of oxidized oils on the absorption coefficient of the light flux, the authors determine the degree of influence of oxidation products on the anti-wear properties.

Experimental studies of friction and wear for piston skirt and cylinder liner materials at hydrodynamic mode with using a friction machine have been carried out. Influence of initial roughness and lubricant on a final micro-relief of contacting surfaces after experiment was investigated. The experimental studies were carried out according to a “roller-pad” scheme. Three brands of motor oil from the main groups for diesel engines were used. The first is from the group of oils made from the sulphurous oil. The second is from the group of oils containing alkylsalicylate additives. The third is from the group of oils with packages of dealkylation phosphate additives. The wear rate and the friction coefficient in each experiment were determined. Experiment results show that the parameters of the equilibrium roughness do not depend on their initial values, but depend on the applied engine oil. The hypothesis, which explains the reasons of relief change of friction surfaces at hydrodynamic mode, is proposed.

The article presents the results of research on effect that SH 15 steel has on processes of oxidation and anti-wear properties of Spectrol Super Universal 15W-40 SF/CC mineral engine oil with the use of a photometric method. This study suggests new factors that account for steel’s effect on thermo-oxidative stability, wear, frictional contact conductance coefficient, forming time of frictional contact, and lubricative properties. The effects of steel on oxidative processes and anti-wear properties of oil and steel’s influence coefficients on oxidation processes and anti-wear properties were researched. It was established that SH 15 steel influences oxidation processes and wear, it can show both catalytical and inhibitory effects as well as oxidation of mineral oil with steel ambiguously affects the volatility of oil, and the formation time of nominal friction contact area was determined from the current recording diagrams on computer display for the duration of plastic and elastoplastic deformations and its electrical conductivity and lubricity due to the products of chemisorption processes occurring on surfaces.

The article is devoted to the development of theory of tribotechnical interaction of a kinematic pair “shaft-sleeve” of the friction bearing of a gas-compressor unit (GCU) on the basis of molecular physics of boundary friction. The aim of the research is achievement and securing of a high level of reliability and safety during the lifecycle of high-loaded friction supports of GCU. A mathematical model describing contact deformations in the pair “shaft-sleeve” of friction bearing has been proposed. The stage of dynamical sliding of the shaft in a bearing sleeve has been considered. The mathematical model of boundary friction of porous heterogeneous surfaces taking into account their geometrical, force and physical and mechanical parameters has been proposed. Lubricating ability of porous heterogeneous surfaces has been researched. The parameters determining contact interaction of surfaces of high-loaded friction support of GCU have been brought out.

The description of the construction of a self-lubricating sliding bearing of modified wood for heavy-duty friction units and manufacturing technology of it are presented in this article. To determine the coefficient of wood friction on steel, the technique was developed and MI-1M machine friction was modernized. Depending on the load the coefficient of sliding is in the range 0.06–0.11. The designed bearing construction allows one to replace not only sliding bearings, but also the rolling bearings in friction units. The main advantage of such bearing constructions is uniform density over a cross section. This density provides a low coefficient of friction and high wear resistance, as well as the ability to absorb abrasive particles and wear products that provides a long-term zero wear of a rider. To reduce the friction coefficient, the lubricant such as the Biol type is put in the metalized timber in the amount of 7–8% by weight of the wood. To impart the increased rigidity of wood, the hardness and wear resistance nanocrystalline cellulose (NCC) in the amount of 0.5–0.8% by the weight of wood is added into the timber together with the lubricant.

Microcapsules based on the product of the interaction of 2,4-toluene diisocyanate and 1,6-hexamethylenediamine containing DOS lubricant inside were synthesized by the method of interfacial polycondenzation in an oil-in-water emulsion. Adding microcapsules containing lubricant to phenylone FS-2 improves its tribological properties. The friction coefficient for composite containing 7% microcapsules is three times lower than that of phenylone without additives. When the friction composite contains microcapsules with a lubricant, the formation of transfer films occurs on the surfaces of friction of AISI 420 steel. The elemental composition of the friction surfaces of AISI 420 steel with FS-2 polymer contained 7% DOS microcapsules composite was investigated by XPS. The presence of the N1s spectrum in the survey spectra indicates the presence on the surface of friction of fragments of the phenylone molecule. On the surface of the steel, there are atoms of the alloying element of chromium, which are partially oxidized. Spectra N1s from the surface without friction and after friction and then from the surfaces after ion etching, demonstrate the preservation of fragments of the phenylone molecule to 15 min of ion etching.

The paper presents the basics of the technology for fabrication of solid lubricant composite ceramic coatings that are basically a ceramic matrix with antifriction fillers based on magnetite, graphite, and molybdenum disulfide, which are formed on the aluminum alloy using the micro-arc oxidation method. It also shows the features of electrophoretic implantation of dispersed particles of magnetite, graphite, and molybdenum disulfide into a ceramic matrix. The authors have experimentally studied the dependence of coating triboengineering properties on the concentration of solid lubricant particles in the electrolyte and temperature conditions in the friction zone. As a result, they have formed the requirements for the composition of the electrolyte used to apply these coatings. The comparative triboengineering tests have shown that synthesized solid lubricating composite ceramic coatings with antifriction fillers have higher antifriction characteristics, a lower friction coefficient, and are more wear resistant compared to unsupported ceramic materials obtained by a traditional technology of anodic spark oxidation. The new synthesized coatings can improve antifriction characteristics of friction surfaces for units operating in the absence of a lubricant by several times. The wear analysis of the obtained coatings has shown that the obtained ceramic coating with the molybdenum disulfide as a filler has the highest antifriction properties. The triboengineering tests of molybdenum disulfide coatings (as a solid lubricant) confirmed the need for the adsorbed protective films on the dispersed phase particle surface during the microarray application of these coatings to improve antifriction properties of the particles.

Based on the experimental data on a composite solid lubricant coating, which can be applied within a wide temperature range and under high loads, has been developed. The coating consists of several layers. The layers differ from each other by the physical and chemical composition and the method of application to the steel surface. The first layer of the composite solid lubricant coating has been obtained using the method of chemical deposition of the nickel-containing layer. The first layer obtained consists of the coating with a polyphase structure, such as nickel-phosphor, nickel, etc. The following layer has been obtained by the application of the water solution of aluminum phosphate and chrome to the surface of the first layer. The last layer is applied on the second layer in the form of the solid lubricant coating. The last layer is a binder with a composition of particles of solid lubricants. The universal technology to form the multilayer composite solid lubricant coating has been developed and its properties have been studied.

In metal cutting, tool wear and restoration of its cutting properties are a significant problem for engineering production. Therefore, the development of a theoretical description of tool wear and its dependence on processing modes is a pressing issue for machine builders. The article offers a version of the mathematical model of wear of cutting tools made of composite hard alloy materials. The model of fatigue wear of carbide cutting tools for steel turning based on the cutting theory is developed in this article. The model takes into account cutting modes, the mechanical properties and the heterogeneity of the material being processed, the geometric parameters of the cutter, the instability of the cutting process, the periodic change in shavings thickness, the width of the cutting layer, the cutting speed and a number of other factors. The proposed approach allows predicting the fatigue wear of cutting tools made of hard alloy, as well as determining the ways to improve the structure of the hard alloy, the shape and geometry of the cutting plates.

The paper assesses the effectiveness of the plastic lubricants use with the addition of ultrafine copper powder to increase the service life of sliding bearings operating in the swinging motion mode. When moving, when the friction force constantly changes the direction of action, the processes of the surfaces wear occur more intensively. Under the operating conditions of such a bearing assembly, the most effective method of increasing service life is the use of modified lubricants with improved anti-wear and anti-friction properties. Tribological studies have established that the introduction of ultrafine copper powder into the composition of basic industrial lubricants significantly improves performance. The use of modified lubricants resulted in a reduction of friction in the bearing assembly to 70% and a decrease in the operating temperature of the assembly to 25%. The studies carried out confirm the theoretical propositions about the positive effect of copper-containing additives on the improvement of anti-wear and anti-friction properties of grease lubricants. The presence of a lubricant that can significantly reduce friction forces reduces the amount of internal stresses and retards the development of fatigue cracks in areas of direction change. The processes of fatigue failure of the surface layers are inhibited by reducing the magnitude of shear stresses at the contact area.

The present research considers the application of magnetorheological fluids as lubricants for journal fluid-film bearings. In order to solve an ever occurring problem of enhancing the performance of rotor machines to meet industrial requirements, a tribomechatronic system is proposed with a journal fluid-film bearing lubricated with a magnetorheological fluid. This type of fluids could be used as a direct actuator for a mechatronic rotor positioning system for rotor machines. As a part of a complex research on tribomechatronic bearings, the present research features a conceptual and a mathematical model of a journal fluid-film bearing that is lubricated with a magnetorheological fluid. The mathematical model is based on the Reynolds equation, and additional expressions take variable viscosity and presence of magnetic field into account. The paper features a two-step verification of the model based on comparison with experimental results by other researchers. It outlines certain peculiarities of the operation of fluid-film bearings lubricated with MRFs and sets directions for further research.